I just ROMed with OmniROM which is a KitKat build. It is basically a vanilla android ROM with a few perks. I personally LOVE it (so much faster and smoother than the stock). But...
1) Camera is not working reliably. I tried to take a Photosphere and now it crashes whenever I open it. On this ROM, google apps (including camera) are flashed separately though, so it is not a huge deal for me. But I did flash the AOSP camera and it doesn't seem to play nice with the hardware. I assume if you flashed the stock camera it'd probably work fine. I might do that eventually. The camera does work with 3rd party apps (I can use focal, but the display is weird. But that might just be Focal itself).
2) ART is not supported, but it is there, and I am too chicken to try it. The option is there but a warning pops up saying basically "use at your own risk". It seems plenty fast without it though.
3) Can't get GPS to work (aGPS does seem to work though...I can get my location on Maps)
Other than that everything seems to be as good or better than normal. Bluetooth works. This was a dramatic improvement over stock, and I am so glad I ROMed. I am using the latest TWRP recovery which itself is awesome.
[ROM] [4.4.x] [OFFICIAL] OmniROM for the TF300T - xda-developers - Yes, it is a 4.4.2 ROM
Edit - Camera is fine, just won't work with the AOSP app. Installed ICS camera from the market and it works fine. Still won't take photospheres though. And I am on ART now and everything seems fine. Same performance improvements I have seen on other Android devices.
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