No, the performance was great. The UI is not unusuable, but pretty frustrating, and as far as I know there's no CEC support in Android (or, at least, their Android build). So as a set top box I don't think it works.
Worse still, you can't really run background services without a lot of hassle, so you also throw away a lot of what makes it compelling as a mini-server.
So by useless I suppose I mean it doesn't do anything very well.
Useless how? Performance was poor, or without a touch screen you weren't able to use it?