User

People tend to transcode to Prores HQ or DNxHD HQX files as proxy media, often depending on what platform they're on (PCs can't make Prores files IIRC), but my research didn't turn up any differences in quality between the two formats, so use whichever you like.
If you want way too much information about proxy formats, here you go....
https://blog.frame.io/2017/02/15/choose-the-right-codec/ https://blog.frame.io/2017/02/13/50-intermediate-codecs-compared/ The second link shows the bitrates of the various codecs and you'll see that Prores HQ and DNxHD HQX are very similar, but note that DNxHD HQ is 8-bit vs DNxHD HQX is 10-bit, and this will likely make a difference so is worth checking if you go the DNxHD route.
With all things, when you make a compressed copy of something you only degrade the quality.  However with high quality codecs like these the degradation will be minimal and likely not a factor in the end result.  As you say, this is about story and storytelling, and I think that the ability to edit with smooth playback will add more to the storytelling than the very slight degradation of the image will detract from it.

If you need to trancode for the reasons you explained I can understand this as a reasonable solution. I tried it a while back and found  an obvious increase in things like banding in smooth tones like skies unless I used one of the highest quality settings with 4.4.4 chroma subsampling but the file sizes got incredibly large. ProRes is after all a lossy compressed codec. Depending on your type of subject matter and how much you need to grade this may or may not be important.

It might not be very easy to do this if you've cut the files before generating proxies. When I do this for my proxy workflow in Resolve, I'm relying on the fact that each proxy file is exactly the same filename and length as its corresponding online media. How would Premiere know that Proxy A corresponds to time 0:05 - 0:15 of file A?
If you have unique timecodes for each file, and have properly carried those over into the proxies, you may be able to do it painlessly, since timecode would indicate which proxies correspond to which segments of the original. I think Resolve's conform abilities might be able to handle this, no clue about Premiere.
In my experience, there won't be much degradation. It might be visible if you pixel peep, but certainly will not be immediately noticeable to the average viewer. It may be worth the cost, especially since at this point the H.264 files are really holding up your ability to finish editing. So I wouldn't worry too much about it--it's a non issue at best, and a necessary evil at worst. But I'd keep those original files around anyway, just in case you find that you need them.

Why are you transcoding? You will loose image quality for a start and Resolve has various methods like Proxies, Optimised media and render cache to enable you to work with easier codecs in the timeline and then render the final result from the original source footage so you don't loose quality.

Great question..   I assumed @User was just using Resolve to generate media for use in some other software, but maybe that's not true?

Cool you found it.  I have lots of those moments!
Also, if you don't want to edit the clips but just want to convert all of them to Prores, then the Media Management tool under the File menu (when the Media page is selected) is a great tool.  It can also export the things only on the timeline too, either the whole clips that appear on the timeline, or the same but also trimming the clips on the timeline and optionally adding extra frames to the start/end of each clip for flexibility in editing later on.

Good article Andrew.  I would like to see you also do an article that is your current top cameras, regardless of release date.  I'm sure you'd provide some interesting commentary and some inclusions from previous years that are still holding their own against the newest releases.  It would be of real value to those who are in the market too.

I use RGrain. It’s better than FilmConverts IMO.
http://rgrain.com/
 

Yeah, me and the GF are trying to keep our eyes open until midnight... another 3.5 hours to go in my part of the world. We may set an alarm just to give us enough time to guzzle some champagne. 
Have you tried grain overlays? I believe Noam Kroll May have some custom ones. 

It might be worthwhile doing a side-by-side comparison of the noise and the film grain, and trying to emulate it with effects.  I have no idea how PP works, but perhaps adding a semi-transparent blur to the grain (or some other simple effect) might get it close enough to do the trick when applied to real footage?

How about using FilmConvert with just the grain added?

I prefer intermediate codec to proxy workflow myself. Never had any problems using CineForm.
Of course transcode is the pain in that workflow, but done and dusted at the start of the process, and surely less extra procedures than proxy anyway?
Of course proxy has its advantages, I just prefer inters.

I always encourage proxy editing simply because there's less processing stress on the computer.  The less the computer has to work the less likely it is to crash or lag.  At least that's my reasoning.
Doing native format editing is okay for really short form projects, but even then I tend to go the proxy route simply because it allows the editing GUI to function more cleanly.
FCP was always breezy with ProRes, but I'm not on FCP at the moment, so...

Stuttering (maybe 5fps) playback of PROXY media to the point audio dropping out during said playback.  These are 1024x540 res PROXY files that were created by the default PROXY settings in PP and created in Adobe Media Encoder.  Bottom line, the new software couldn't playback those clips.
My issues were happening on an older machine, but the older machine could handle the exact same project just fine in 2017.  Once that project was  loaded into 2019, nada.  All settings were identical from the project in 2017 to the project in 2019, including all preferences.  My conclusion after internet sleuthing was that 2019 just demands more processing overhead for some reason.  Don't really care why this is, it just does.  That's my experience and it caused workflow issues.
So....that and some random unrecoverable crashes that I hadn't seen before made me nope right on outta 2019.  I got better things to do than trouble shoot beta-level software.
Couple of nice features that come with 2019, but without a certain level of workflow stability, just no no no.
Yes and no. 
When I'm pulling and pushing the grade it's usually during the coloring stage --and proxies are turned off at that point anyway so you're seeing a pretty accurate rendition of what you're gonna get from your source footage+grade.
Sometimes I'll quick color grade a proxy too as I'm editing; it holds together enough to do the basics.  And, as mentioned, all fine tuning I do with the source footage anyway.
Basically I'm saying that, for me, working with proxies doesn't really affect the coloring workflow.  It does, however, make the basic editing so much more pleasant.  Just scrolling footage in the thumbnails with no lag is such a blessing.

I am editing my current doc with PP and I'm getting it done. My anecdotal experience says it can handle large projects (100hr+ of footage) such as a feature length documentary, but with caveats.
1) You should use proxies
2) don't do any complicated compositing
3) use an old version (I went backwards and am using CC 2017.1.2)
2019 just about killed me for a week before I did a XML export and took my project to an earlier version of Premiere.
Premiere Pro crashes, but I can't say more or less than my FCP used to.  Still, PP just never feels "solid."  There's no objective way to qualify that assertion, you just need to use it to get a gut-level feeling about it.  That feeling has never been reassuring for me. 
Also, the way PP demands media to be loaded into a project in order to migrate sequences is, augh, such a pita!  That mundane detail might seem trivial to the uninitiated, but to those of us trying to move edits across different editing seats it's absolutely horrendous.

My understanding is that most people currently use Resolve for grading, which means round-tripping to Resolve via the XML export, doing the grading, but then rendering out the graded individual clips which are then swapped into the original project in the editing software to replace the ungraded clips.  In this sense, PP (or FCPX) won't be too worried or motivated to make sure that all the dissolves and effects make it out to a Resolve timeline.  I'd suggest that BM would be very interested in making sure things import as well as possible, but BM is currently adding entirely new screens and hundreds of new features in each major release, so they definitely have their fair share of bugs too.
I've heard that there's normally some work to get all the media linked in Resolve, but it has some quite good features for linking clips quite easily (something like highlight clips -> Relink media -> select "include sub-folders" and point it at a folder with all your footage in it) so if you do need to relink files it's not necessarily a big job.  There's lots of advice around for solving strange importing problems so if you want to pursue it at some point then google can help.
Ouch - I'd say that using contacts to circumvent their prioritisation of bugs is a bad idea, but considering how buggy people say it is, maybe that process isn't working so well!
I remember when those colour features were added.  I saw a bunch of Youtubers had released videos with exciting titles and I thought the added features must be really great - then I saw them and actually laughed out loud.  If you double (or triple) the available features then it looks like a huge improvement, but to Resolve users they just went from having 1% of the features to 2%, so it's not so exciting from our perspective 

After a couple years on other software I decided to give PS and LR a go the other day and signed up for a subscription. I moved from the UK to the Netherlands and it took Adobe support about two hours to change my account. It was very much like the thread above. A trip to hell. 
Made me immediately regret getting back on Adobe. 
 

Same here, one week worth of editing, and the fucker wouldn't start rendering it out. In the end mpeg and xml was the only thing what I could still save it in ---> could recover of what i had in resolve. It's just too much stress

It might be interesting to do a Resolve stress test to see if it can handle big projects.
Maybe someone who finishes a big project can pull it into Resolve and render it out and give their impressions?
I'd do one but I don't have a real project that's big enough to be a genuine test.

I edit in Cineform rather than h.264, which I think really helps performance.
Media Encoder is also very good, I find.

Some other notes:

Dynamic link (Premiere <--> After Effects) is quite a system resource hog.  I tend to only use it if it's going to really benefit the project workflow.  For quick stuff I just use the old-fashioned render-out method, which is rock solid.
In addition to the above, I have had some render issues with complex projects.  I have had to mitigate this on occasion by rendering out in high-quality chunks (or layers), recombining on a timeline and then re-rendering.  So that's another big minus point - but that's only been occasional, when working with massive files on particularly complex timelines. 

I have had a pretty crash-free and bug-free experience with creative cloud personally.
After Effects is completely stable as far as I'm concerned.
I've had some minor niggles with premiere, and one serious problem - occasional hangs on using 'save as', which is annoying but can be mitigated with a workaround.
Audition roundtrip works a treat.
Photoshop and illustrator integration and stability are great.
All in all is a fantastic suite, though whether the pricing is fair, I'm not sure. Certainly as a professional the price is easily worth paying.

It'll be stable in 3-4 patches... ?

Try exporting to xml and then importing to resolve, nothing to lose!
I switched over recently and I haven't noticed the actual performance being better than premiere in terms of stutters during 4k playback but at least I don't get the glitch where I can't save and premiere hangs for 30mins with the file explorer dialogue is open...
Obviously there's some bugs but I'm trying to escape the Adobe universe.

I feel your pain. Between Premiere unstability and Flash vulnerabilities, I have a strong distrust of Adobe myself. I use Resolve for editing these days. My biggest project is ~5,000 files / 500 GB and Resolve is handling it just fine. Each of the files actually is imported both in full res and a proxy, so there's closer to 10,000 imported files. Not sure how that scales against your needs...

No problem! Good luck!