I'm still on the 4/20 build, but I've been using it for a few days now and I have to say, the only bugs I'm finding are obviously the camera, and certain graphical glitches at certain times. It's hard to explain really, certain apps though will make the screen flicker about a bit, it almost looks like it's displaying a phone sized version of the app and then it immediately maximizes to tablet size. The status bar flickers about too. No force closes though, which is good. And ICS runs so much better than HC