Marcio Kabke Pinheiro

G9 II for sure. With PDAF, will be an interesting camera - unfortunately, not for me anymore.

(if it was a GX10, yeah, I would be tempted)

G9 II for sure. With PDAF, will be an interesting camera - unfortunately, not for me anymore.

(if it was a GX10, yeah, I would be tempted)

I don't mind manufacturers segmenting by price, in a way that's sort-of reasonable, as long as it doesn't go too far in the direction of being anti-competitive.  
The thing I mind is that they also segment on camera size.  If you want great image quality then the cameras just become unwieldy and attention-grabbing.  Modern technology makes everything smaller over time, but they ate up that size advantage with extra megapixels.
Of course, the elephant in the room with overheating is that it's caused by the blind pursuit of more and more pixels.  Of course, some people have convinced themselves of the "need" for more pixels, but the frilly pink dress that the elephant is wearing that no-one will discuss is that you can't see anything more than 720p (at best) on a smartphone, which is the primary viewing device for most of what is being filmed by these people.

About all these hot new cameras (pun intended): I agree that would be much better them to not overheat. And for me is intentional: it is segmentation.

For instance: the X-S20, the A6700 and both the new A7C have a plastic back panel, behind the LCD. If they really want to help dissipating heat, they could do a metal back panel. Specially in the Fuji case, where you can specifically put a fan there.

Panasonic also showed in the S5II that you can incorporate a discreet fan without raising the cost.

It is segmentation. Same thing with the LCD mechanism from the A7RV - solve one for all the tilt / flip debacle, should be standard for all new cameras. Fuji also made a similar solution with the XT100. But...want more, pay more.

If you want to pay less, you have to deal with the limitations. I could use my 1.0 liter car to tow a heavy trailer? For sure, but will not be a very good experience.

Not defending the manufacturers, but it is how it works in all markets. Will be this until someone breaks the mold and all need to follow.

Well, quick test, very unscientific one, but here we go:

6.2k 30p, Long Gop 10bit 4:2:2 360mbps. Camera on Boost mode, filming a TV screen with a movie playing to give a harder time for the codec (if you test in a static shot, in theory the encoding work could be pretty minimal in a long gop).  Face detect running too, getting faces on the tv screen.

Temperature set on the menus to "High", back LCD in open position.

Extreme Pro V30 200 Mbps card. Room temperature, 24 deg celsius, 70% humidity.

First overheating warning (yellow) appeared around the 25 minutes mark. The red warning appeared very soon after, around 29 minutes. But the camera never shutdown, ran for 45 minutes until the 128gb card was full.

Camera hot to touch, much than usual, but not close to cause a burn. With an infrared thermometer (not a very precise one) marked around 38 degrees on the back, where the fan could attach. The bottom plate was hotter, arounf 42 degrees, but you can hold the camera on the bottom without disconfort. The grip was hot too, around 40 degrees - removed the battery and card right after, battery hot but no so much, card was hotter.

Was expecting worse, since the red warning appeared so soon. Since the battery was a source of heat, probably feeding energy with a PD charger could extend the run times (and probably mandatory if you want continuous takes bigger than this, albeit the battery just dropped one bar).

Will do the same test in a hotter day under the sun (probably some months from now, it's winter here). Guess that yeah , a shutdown is a possibility under hot sun.

Well, quick test, very unscientific one, but here we go:

6.2k 30p, Long Gop 10bit 4:2:2 360mbps. Camera on Boost mode, filming a TV screen with a movie playing to give a harder time for the codec (if you test in a static shot, in theory the encoding work could be pretty minimal in a long gop).  Face detect running too, getting faces on the tv screen.

Temperature set on the menus to "High", back LCD in open position.

Extreme Pro V30 200 Mbps card. Room temperature, 24 deg celsius, 70% humidity.

First overheating warning (yellow) appeared around the 25 minutes mark. The red warning appeared very soon after, around 29 minutes. But the camera never shutdown, ran for 45 minutes until the 128gb card was full.

Camera hot to touch, much than usual, but not close to cause a burn. With an infrared thermometer (not a very precise one) marked around 38 degrees on the back, where the fan could attach. The bottom plate was hotter, arounf 42 degrees, but you can hold the camera on the bottom without disconfort. The grip was hot too, around 40 degrees - removed the battery and card right after, battery hot but no so much, card was hotter.

Was expecting worse, since the red warning appeared so soon. Since the battery was a source of heat, probably feeding energy with a PD charger could extend the run times (and probably mandatory if you want continuous takes bigger than this, albeit the battery just dropped one bar).

Will do the same test in a hotter day under the sun (probably some months from now, it's winter here). Guess that yeah , a shutdown is a possibility under hot sun.

Well, quick test, very unscientific one, but here we go:

6.2k 30p, Long Gop 10bit 4:2:2 360mbps. Camera on Boost mode, filming a TV screen with a movie playing to give a harder time for the codec (if you test in a static shot, in theory the encoding work could be pretty minimal in a long gop).  Face detect running too, getting faces on the tv screen.

Temperature set on the menus to "High", back LCD in open position.

Extreme Pro V30 200 Mbps card. Room temperature, 24 deg celsius, 70% humidity.

First overheating warning (yellow) appeared around the 25 minutes mark. The red warning appeared very soon after, around 29 minutes. But the camera never shutdown, ran for 45 minutes until the 128gb card was full.

Camera hot to touch, much than usual, but not close to cause a burn. With an infrared thermometer (not a very precise one) marked around 38 degrees on the back, where the fan could attach. The bottom plate was hotter, arounf 42 degrees, but you can hold the camera on the bottom without disconfort. The grip was hot too, around 40 degrees - removed the battery and card right after, battery hot but no so much, card was hotter.

Was expecting worse, since the red warning appeared so soon. Since the battery was a source of heat, probably feeding energy with a PD charger could extend the run times (and probably mandatory if you want continuous takes bigger than this, albeit the battery just dropped one bar).

Will do the same test in a hotter day under the sun (probably some months from now, it's winter here). Guess that yeah , a shutdown is a possibility under hot sun.

I'm using 10-bit 4:2:0 in my X-S20 because 10-bit 4:2:2 have no hardware decoders on Nvidia cards, only 10-bit 4:2:0. 
From what I've searched, keying, like you said, is the most visible difference, and contrast on the edges (hence the better keying in 4:2:2). Looks like some very pushy grades are better with 4:2:2, too.

For me (personal use), I think that 4:2:0 will be enough - never had a 10-bit camera before, I guess that 8 to 10 bit is a much more noted upgrade.

Well, quick test, very unscientific one, but here we go:

6.2k 30p, Long Gop 10bit 4:2:2 360mbps. Camera on Boost mode, filming a TV screen with a movie playing to give a harder time for the codec (if you test in a static shot, in theory the encoding work could be pretty minimal in a long gop).  Face detect running too, getting faces on the tv screen.

Temperature set on the menus to "High", back LCD in open position.

Extreme Pro V30 200 Mbps card. Room temperature, 24 deg celsius, 70% humidity.

First overheating warning (yellow) appeared around the 25 minutes mark. The red warning appeared very soon after, around 29 minutes. But the camera never shutdown, ran for 45 minutes until the 128gb card was full.

Camera hot to touch, much than usual, but not close to cause a burn. With an infrared thermometer (not a very precise one) marked around 38 degrees on the back, where the fan could attach. The bottom plate was hotter, arounf 42 degrees, but you can hold the camera on the bottom without disconfort. The grip was hot too, around 40 degrees - removed the battery and card right after, battery hot but no so much, card was hotter.

Was expecting worse, since the red warning appeared so soon. Since the battery was a source of heat, probably feeding energy with a PD charger could extend the run times (and probably mandatory if you want continuous takes bigger than this, albeit the battery just dropped one bar).

Will do the same test in a hotter day under the sun (probably some months from now, it's winter here). Guess that yeah , a shutdown is a possibility under hot sun.

Will do a test with mine here - not the best conditions now (the temperature here dropped to around 23oC), and only have a V30 card (a 200Mbps Sandisk Extreme Pro that until now worked without glitches with 6.2k, but probably will generate more heat).
But will try to record in Long GOP instead of ALL-I (this probably generates even more heat), with the LCD open (since the back was made to get the fan, probably there is some heat spreader there).

I'm using 10-bit 4:2:0 in my X-S20 because 10-bit 4:2:2 have no hardware decoders on Nvidia cards, only 10-bit 4:2:0. 
From what I've searched, keying, like you said, is the most visible difference, and contrast on the edges (hence the better keying in 4:2:2). Looks like some very pushy grades are better with 4:2:2, too.

For me (personal use), I think that 4:2:0 will be enough - never had a 10-bit camera before, I guess that 8 to 10 bit is a much more noted upgrade.

I suspect that a primary problem with fora is that over time they become too one-sided, narrow minded and restrictive. Reduser doesn’t tolerate criticism - it would be fabulous to engage in (and learn from) genuine debate about braw vs. redcode etc. But that can’t happen because anyone who extols the virtues of braw will undoubtably be met with hostility. Here, it possibly isn’t a great idea to discuss Bloom’s reviews - why not? They are often informative and entertaining. But… Fora tend to become echo chambers and new, different or dissenting voices leave (voluntarily or otherwise). I fear that the majority of users go to their forum of choice (photo, automobile, hifi, whisky etc.) simply to have their views (or buying choice) reinforced and validated. Lots of us remember interesting (?), useful (?) or controversial (?) contributions from those who are no longer here. We might not have agreed with or liked or even understood them (young Zach…) but they presenting a range of opinion to keep things lively. And why don’t the “experts” (eg JB and, yes, even PB) pop in from time to time to share and discuss ideas? This space manages to retain neutrality with respect to brands and I think that is possibly unique. But - and without being deliberately critical - it has also driven people away. Why? 
Personally I’d like to see Andrew promote a topic of the month - eg “does 8 or 10 bit really matter?” and let a thoughtful, knowledgable and informative debate develop. And develop without being lost in “what camera should I use/buy?” or similar posts. Or a discussion about audio options at relevant and appropriate prices and level or expertise. The forum then becomes a place of genuine learning and debate not simply an exchange of opinions. But perhaps I miss the point…

Just to get back on topic...
The trend isn't limited to photo, video or filmmaking forums, it's all forums...
A friend recently reminisced how he used to talk to fans of his favourite band online all the time and do meet-ups.
The band's unofficial forum was a hub for this, but now it doesn't even exist.
It is just people on a Facebook group now, posting pics and pressing like.
This is due to smartphones and the fact they lack a proper keyboard for longer form content and interactions.
Plus a few social media apps have replaced .com websites.
Hope to see a reversal of it as this is not using the internet to its true potential.
People should put the phone down and get back online via a laptop or desktop machine instead!

Another point that is bothering me right now: the lack of testing some details point, coupled together with (looks like) the companies refusing to answer some technical details. Some examples:

- Electronic shutter for stills: what are the penalties, if any, besides rolling shutter? In the past, I remember some smaller Panasonics reverting to a lower bit depth when using it. Tested in my current cameras, the RAWs have the full bit depth, but it is real bit depth or less bits wrapped in a bigger bit depth "container"? There is a dynamic range penalty? Never find a correct (and justified) answer.

- Always is said that a 4k image downsampled from a larger read in camera render a better image than a 4k crop of the sensor. Looks logical - but why the image quality from the Open Gate cameras (hence, using a 1:1 readout of the sensor) are showing no image penalty?

- Which cameras have (or not) plug-in power for using external mics? Good luck to find out.

Every review is the same topics over and over. Taking the X-S20 for example: no one mentioned that the Face / Eye AF is not only better, but is totaly different than before, you have to use is a very different way. No comparison between the penalties of using lower data bitrates - is 360mbps and 200mbps much different? Or 10-bit 4:2:2 and 10-bit 4:2:0 - I've discovered this is a HUGE topic for Windows users this week, because Nvidia cards only have decoders for 10 bit 4:2:0, you could have the best RTX 4xxx card and your 10 bit 4:2:2 footage will only decode using CPU; and only the newer Intels CPUs with iGpu have hardware decoders 10 bit 4:2:2.

Everything is very shallow. 

I mean not all brands have overheating issues, so... 😉

In theory, yes, these things are all true, but not for this camera.
Here's the video posted earlier by @SRV1981...  check out the outside testing.
In case you don't want to watch a couple of minutes of video, here's the results:
Tested in North Carolina in mid-morning 80F and humid, in direct sun Tested from cold in AC all night Tested in 4K XAVCS, auto temp set to high, screen open Tested at 24p Overheated in 22 minutes Let me summarise: camera is not reliable.  Will it work for some people in some conditions?  Sure.  Will it work for you?  No way to tell.
There's no way I'd buy a camera like this, because you would have to know you can't record with it in the sun (even at indoor temps!), or in a hot building, or at 60p, etc etc

Another point that is bothering me right now: the lack of testing some details point, coupled together with (looks like) the companies refusing to answer some technical details. Some examples:

- Electronic shutter for stills: what are the penalties, if any, besides rolling shutter? In the past, I remember some smaller Panasonics reverting to a lower bit depth when using it. Tested in my current cameras, the RAWs have the full bit depth, but it is real bit depth or less bits wrapped in a bigger bit depth "container"? There is a dynamic range penalty? Never find a correct (and justified) answer.

- Always is said that a 4k image downsampled from a larger read in camera render a better image than a 4k crop of the sensor. Looks logical - but why the image quality from the Open Gate cameras (hence, using a 1:1 readout of the sensor) are showing no image penalty?

- Which cameras have (or not) plug-in power for using external mics? Good luck to find out.

Every review is the same topics over and over. Taking the X-S20 for example: no one mentioned that the Face / Eye AF is not only better, but is totaly different than before, you have to use is a very different way. No comparison between the penalties of using lower data bitrates - is 360mbps and 200mbps much different? Or 10-bit 4:2:2 and 10-bit 4:2:0 - I've discovered this is a HUGE topic for Windows users this week, because Nvidia cards only have decoders for 10 bit 4:2:0, you could have the best RTX 4xxx card and your 10 bit 4:2:2 footage will only decode using CPU; and only the newer Intels CPUs with iGpu have hardware decoders 10 bit 4:2:2.

Everything is very shallow. 

Another point that is bothering me right now: the lack of testing some details point, coupled together with (looks like) the companies refusing to answer some technical details. Some examples:

- Electronic shutter for stills: what are the penalties, if any, besides rolling shutter? In the past, I remember some smaller Panasonics reverting to a lower bit depth when using it. Tested in my current cameras, the RAWs have the full bit depth, but it is real bit depth or less bits wrapped in a bigger bit depth "container"? There is a dynamic range penalty? Never find a correct (and justified) answer.

- Always is said that a 4k image downsampled from a larger read in camera render a better image than a 4k crop of the sensor. Looks logical - but why the image quality from the Open Gate cameras (hence, using a 1:1 readout of the sensor) are showing no image penalty?

- Which cameras have (or not) plug-in power for using external mics? Good luck to find out.

Every review is the same topics over and over. Taking the X-S20 for example: no one mentioned that the Face / Eye AF is not only better, but is totaly different than before, you have to use is a very different way. No comparison between the penalties of using lower data bitrates - is 360mbps and 200mbps much different? Or 10-bit 4:2:2 and 10-bit 4:2:0 - I've discovered this is a HUGE topic for Windows users this week, because Nvidia cards only have decoders for 10 bit 4:2:0, you could have the best RTX 4xxx card and your 10 bit 4:2:2 footage will only decode using CPU; and only the newer Intels CPUs with iGpu have hardware decoders 10 bit 4:2:2.

Everything is very shallow. 

Finally got some time to navigate all the menu and do some quick tests. Call me impressed.

Surprise one: one little old desire (that nobody mentioned in the reviews) was that now the "3d" electronic level could be enabled pemanentely on the screen / EVF; in the X-S10 - and I guess in all the last generation's Fujis - only the horizontal level was permanent, the 3D version should be activated by a custom button, and disappeared after taking a shot.

Surprise two: a new focus assist tool, only in video mode - Focus Meter. Is a "needle gauge" that shows where to turn the focus ring to bring the image in focus, and that could be used in conjunction with peaking. Works very well and very accurately.

And finally, the AF. The face / eye AF interface and working mode was completely changed form the 4th gen Fuji's. In these (X-S10, X-T4, etc), when face / eye AF is on, the camera selects a face / eye and shows it on the screen in green, the other faces are marked with grey boxes, and you could change the face to focus with the joystick. In theory, a good system - until you hit record, and the camera goes haywire changing the face focused at will. For me, with more than one face on the frame, was unusable.

Now, you choose a area box (that you could resize), and the camera will focus on the closest face of the box. Period. And tends to stick quite a bit in that face before switching to other. Not a perfect system - did not tested the worst situation, with all other people standing in place and the focused person going to the edge of the frame, far from the box, which in theory will make the camera changing the face focused - but if you keep the subject in the same spot of the frame, or move the box with the joystick, works perfectly.

There are more subtleties to discover - one test was filming my wife's father, my wife and my daughter playing in our living room, tracking my daughter (an electric 4 year old), a case which the X-S10 failed completely; the focus point moved from person to person if they are close. With the X-S20, started tracking my daughter, and NEVER let her go. Focus spot on 100% of the time. And with an unexpected behaviour when my daughter got very close to my wife's father, instead of jumping faces, the old gray box appeared on his face, but the AF was kept on my daughter. One touch on the joystick, and then he was in focus - even with my daughter closer to the AF box. Another touch, returned to my daughter. Just as I wanted to be.

The detection is much improved too. In the X-S10, if the person turns and the face did not appear, the camera reverts to the original AF mode. The X-S20 recognizes the back of a head - when the person turns, it starts tracking the back of the head. The person turns back, it revert to the eyes again. And the face / eye detection works in much farther distances than before, and gathers eye / face instantly.

Is a completely new behaviour, much, much better than before.

Not great and getting worse every year.
Glasses wearer; varifocals for every day/work and reading glasses for editing.
Ideally I’d like laser at some point but not happening any time soon.
Lower light especially it really begins to deteriorate…
I am actually debating right now whether to go with the weight of a small monitoring screen for my principle video (S5ii) unit just because of this.
Never been a fan of rigging stuff out too much as a hybrid shooter but right now, I am more back in the camp of using my 3 units as:
Static/gimbal pure video
Roaming video
Stills plus occasional video
So having the biggest, brightest and most detailed rear LCD is quite important to me, mainly for the MF video side of things.

I've worn varifocals (every day) for longer than I can remember - at least 10 years.
As MrSMW said, the first time you wear them it takes a few days - at least - to adapt to them (and some people don't like/can't adapt to them). 
Personally I really like them and wouldn't have anything else now.
I always buy the varifocal lenses with the largest usable lens areas (near, mid, far) the optician offers - it  makes a big difference to the usability. They are often the most expensive but for something I use all day, every day I think it's worth it. Much better to spend the money on the lenses than expensive fancy frames, IMHO. It's like buying pro-grade camera zoom lenses versus kit zooms - the performance is less compromised.
Like MrSMW, I use the Specsavers chain in the UK - this is their guide to varifocals - https://www.specsavers.co.uk/glasses/glasses-lenses/varifocals (I use their 'Tailor-made' lenses)
Note it's more critical for varifocal lenses to be positioned correctly in relation to the eye pupil than single-vision lenses, so make sure the optician adjusts the frames to suit you when you get them.

Finally got some time to navigate all the menu and do some quick tests. Call me impressed.

Surprise one: one little old desire (that nobody mentioned in the reviews) was that now the "3d" electronic level could be enabled pemanentely on the screen / EVF; in the X-S10 - and I guess in all the last generation's Fujis - only the horizontal level was permanent, the 3D version should be activated by a custom button, and disappeared after taking a shot.

Surprise two: a new focus assist tool, only in video mode - Focus Meter. Is a "needle gauge" that shows where to turn the focus ring to bring the image in focus, and that could be used in conjunction with peaking. Works very well and very accurately.

And finally, the AF. The face / eye AF interface and working mode was completely changed form the 4th gen Fuji's. In these (X-S10, X-T4, etc), when face / eye AF is on, the camera selects a face / eye and shows it on the screen in green, the other faces are marked with grey boxes, and you could change the face to focus with the joystick. In theory, a good system - until you hit record, and the camera goes haywire changing the face focused at will. For me, with more than one face on the frame, was unusable.

Now, you choose a area box (that you could resize), and the camera will focus on the closest face of the box. Period. And tends to stick quite a bit in that face before switching to other. Not a perfect system - did not tested the worst situation, with all other people standing in place and the focused person going to the edge of the frame, far from the box, which in theory will make the camera changing the face focused - but if you keep the subject in the same spot of the frame, or move the box with the joystick, works perfectly.

There are more subtleties to discover - one test was filming my wife's father, my wife and my daughter playing in our living room, tracking my daughter (an electric 4 year old), a case which the X-S10 failed completely; the focus point moved from person to person if they are close. With the X-S20, started tracking my daughter, and NEVER let her go. Focus spot on 100% of the time. And with an unexpected behaviour when my daughter got very close to my wife's father, instead of jumping faces, the old gray box appeared on his face, but the AF was kept on my daughter. One touch on the joystick, and then he was in focus - even with my daughter closer to the AF box. Another touch, returned to my daughter. Just as I wanted to be.

The detection is much improved too. In the X-S10, if the person turns and the face did not appear, the camera reverts to the original AF mode. The X-S20 recognizes the back of a head - when the person turns, it starts tracking the back of the head. The person turns back, it revert to the eyes again. And the face / eye detection works in much farther distances than before, and gathers eye / face instantly.

Is a completely new behaviour, much, much better than before.

Finally got some time to navigate all the menu and do some quick tests. Call me impressed.

Surprise one: one little old desire (that nobody mentioned in the reviews) was that now the "3d" electronic level could be enabled pemanentely on the screen / EVF; in the X-S10 - and I guess in all the last generation's Fujis - only the horizontal level was permanent, the 3D version should be activated by a custom button, and disappeared after taking a shot.

Surprise two: a new focus assist tool, only in video mode - Focus Meter. Is a "needle gauge" that shows where to turn the focus ring to bring the image in focus, and that could be used in conjunction with peaking. Works very well and very accurately.

And finally, the AF. The face / eye AF interface and working mode was completely changed form the 4th gen Fuji's. In these (X-S10, X-T4, etc), when face / eye AF is on, the camera selects a face / eye and shows it on the screen in green, the other faces are marked with grey boxes, and you could change the face to focus with the joystick. In theory, a good system - until you hit record, and the camera goes haywire changing the face focused at will. For me, with more than one face on the frame, was unusable.

Now, you choose a area box (that you could resize), and the camera will focus on the closest face of the box. Period. And tends to stick quite a bit in that face before switching to other. Not a perfect system - did not tested the worst situation, with all other people standing in place and the focused person going to the edge of the frame, far from the box, which in theory will make the camera changing the face focused - but if you keep the subject in the same spot of the frame, or move the box with the joystick, works perfectly.

There are more subtleties to discover - one test was filming my wife's father, my wife and my daughter playing in our living room, tracking my daughter (an electric 4 year old), a case which the X-S10 failed completely; the focus point moved from person to person if they are close. With the X-S20, started tracking my daughter, and NEVER let her go. Focus spot on 100% of the time. And with an unexpected behaviour when my daughter got very close to my wife's father, instead of jumping faces, the old gray box appeared on his face, but the AF was kept on my daughter. One touch on the joystick, and then he was in focus - even with my daughter closer to the AF box. Another touch, returned to my daughter. Just as I wanted to be.

The detection is much improved too. In the X-S10, if the person turns and the face did not appear, the camera reverts to the original AF mode. The X-S20 recognizes the back of a head - when the person turns, it starts tracking the back of the head. The person turns back, it revert to the eyes again. And the face / eye detection works in much farther distances than before, and gathers eye / face instantly.

Is a completely new behaviour, much, much better than before.

Finally got some time to navigate all the menu and do some quick tests. Call me impressed.

Surprise one: one little old desire (that nobody mentioned in the reviews) was that now the "3d" electronic level could be enabled pemanentely on the screen / EVF; in the X-S10 - and I guess in all the last generation's Fujis - only the horizontal level was permanent, the 3D version should be activated by a custom button, and disappeared after taking a shot.

Surprise two: a new focus assist tool, only in video mode - Focus Meter. Is a "needle gauge" that shows where to turn the focus ring to bring the image in focus, and that could be used in conjunction with peaking. Works very well and very accurately.

And finally, the AF. The face / eye AF interface and working mode was completely changed form the 4th gen Fuji's. In these (X-S10, X-T4, etc), when face / eye AF is on, the camera selects a face / eye and shows it on the screen in green, the other faces are marked with grey boxes, and you could change the face to focus with the joystick. In theory, a good system - until you hit record, and the camera goes haywire changing the face focused at will. For me, with more than one face on the frame, was unusable.

Now, you choose a area box (that you could resize), and the camera will focus on the closest face of the box. Period. And tends to stick quite a bit in that face before switching to other. Not a perfect system - did not tested the worst situation, with all other people standing in place and the focused person going to the edge of the frame, far from the box, which in theory will make the camera changing the face focused - but if you keep the subject in the same spot of the frame, or move the box with the joystick, works perfectly.

There are more subtleties to discover - one test was filming my wife's father, my wife and my daughter playing in our living room, tracking my daughter (an electric 4 year old), a case which the X-S10 failed completely; the focus point moved from person to person if they are close. With the X-S20, started tracking my daughter, and NEVER let her go. Focus spot on 100% of the time. And with an unexpected behaviour when my daughter got very close to my wife's father, instead of jumping faces, the old gray box appeared on his face, but the AF was kept on my daughter. One touch on the joystick, and then he was in focus - even with my daughter closer to the AF box. Another touch, returned to my daughter. Just as I wanted to be.

The detection is much improved too. In the X-S10, if the person turns and the face did not appear, the camera reverts to the original AF mode. The X-S20 recognizes the back of a head - when the person turns, it starts tracking the back of the head. The person turns back, it revert to the eyes again. And the face / eye detection works in much farther distances than before, and gathers eye / face instantly.

Is a completely new behaviour, much, much better than before.

Indeed. My X-S20 just arrived, and have 6k 10-bit 4:2:2 with good(ish?) AF and IBIS in a body roughly bigger than a GX85. 4-5 years ago, it was unthinkable.

But ergos are all over the place - this a thing that could improve. I've taken my GH2 out of the dry box to use it to test the last m43 lenses that I'm selling. First, this thing is freaking small - since the GH3 we forgot how small it was. And, even small...look at the image.

Left dial, focus area, with a lever to switch the AF mode. Main dial (with 3 custom positions!) with two lever, one to set drive mode and other is the on-off switch (in a amazing position, very easy to access with the thumb). 

I miss this a lot.

(and good internal mics - the GH2 mics are VERY good, much better than all the other Pannys that I had (never had a GH5 or G9, though).