I'm very happy with how games look on my 4805 (852x480). I feed it a 720p signal from my radeon 9800pro and it scales very nicely down to 480p. I haven't taken any decent screenshots of it besides a couple quick ones of me walking around an empty CS:S map (pics in sig under "projector").
I don't play games on it really, I've just tried it out a couple times. My not playing on it has nothing to do with the image quality, it's just more of a hassle to play without a nice desk to put my mouse and keyboard on. How I have it setup now, I have to have my keyboard in my lap and my mouse on my futon if I want to play on the projector... less than ideal 😉