Had one of my first intense shoots with the S9; this was a concert with a well-known rapper in the Christian Music scene. Used the Panasonic S9 with my Sigma 18-35 (haven't sold it yet). So was using the APSC crop mode; honestly this is a great faux-APSC camera, image quality still phenominal and noise performance isnt bad. I filmed using the 3.3k 4:3 mode which is lovely and allowed me to really easy make a 9:16 edit while still framing for 16:9 or 2:35:1 as well. It's nice too that I can do 48p or 60p without a FOV increase. I am content with this mode so don't have a massive urge to sell my Sigma 18-35 and get proper full frame glass. Eventually i will though. Double aspect ratio markers on the S9 is sweet; I had a 2:35:1 AND 9:16 aspect ratio marker going at once making framing for both mediums so easy. IBIS is so good; I filmed 90% with e-stabilization set to high; this did crop pretty heavy but you forget about it when shooting, and the performance was so good I rarely had to post-stabilize and could easily replicate gimbal tracking shots with a heel-toe walk and holding the camera a bit loosely. The cage and hand-grip definitley helps, and I don't find the camera to be uncomfortable; the Sigma 18-35 is definitely front heavy, but the setup is still a lot more comfortable than my old Z6 with the Atomos Ninja V bolted on. I will say over time the smallrig handle seems to come slightly loose so i have to tighten it every now and then, but when not shooting I also tend to hold the camera in one hand by the grip.
Other notes:
Battery life is great. Only used two batteries for the entire shoot filming multiple concerts over a few hours. Didnt' even fully run through the second.
Lack of viewfinder is not a dealbreaker for me as I only do video; screen could use to be a bit brighter but still usable in direct sunlight.
The rear dial feels so cheap; you can easily nudge it half-way between its click points. I don't like it. At least it's very functional. I do find the function button placements to be good, and i can efficiently change settings. A joystick would have been cool.
Lack of hot-shoe a non-issue for me as I am 98% video. If I really need it I can whip out my Nikon Z6 for photo work.
Camera never overheated once, and it was a very hot day.
Definitely love this camera. I do see myself picking up an S5 II on ebay down the line, but I don't see myself ever needing anything better; just would like weather sealing and a more robust build. But the S9 is still totally usable as an A-CAM and can work really well in that capacity if your needs are comparable to mine. Given that I paid $860, its easy to overlook the flaws of this camera.