I ended up buying a C4 since they were on sale and at this point price protection for next 60 days so whatever. Got a 5 year warranty to cover burn in, since I'm still a bit worried about OLED longevity.
Overall, compared to my high end IPS monitor, I'll be honest it's obviously better but not immediately noticeable. Because the IPS is brighter it tends to balance the same scenes differently but you end up with what I guess I'd call true contrast on the OLED vs brute force on the IPS. Viewing angles are technically better, but really dark and black scenes are the only thing very noticeable.
One thing I'm noticing is nVidia drivers or lossless scaling app don't like something at some point, if will toss up a partial corrupted frame but only in one specific game. This doesn't happen on my IPS though. So suspecting it could be that thing with VRR/GSync that some people say happens, but it seems less likely since my 4090 is very good at keeping it pegged close to 144 fps at all times. Still testing random things otherwise.
I also tried that ColorControl App but it seems to only work sometimes and has some limitations, namely that it used mobile wakeonlan instead of the HDMI based one and since it only seems to fire on login (guessing used Windows service scheduler), it seems to need to be set to monitor 2. Will have to keep fiddling with that.
Biggest problem is fucking LG remotes work on anything and now I have 3 LG TVs in this room and I had to electrical tape the IR sensor or else it gets turned on/off/volume whenever the wife changes the big TV on the wall. Annoying it's 2024 and they haven't added a way to isolate channels or anything.
Overall, though, it's really nice picture quality and since there's not an equivalent monitor (Asus 42" is EoL and I think a C2 panel), there's really no other option. I might "regret" if they come out with something in a year or two, but I guess I can always do a warranty claim at some point to trade up.