Peter Weller was great...I said "in movements"...he looked like he was dong the robot most of the time, and in today's tech savy would that sort of jerky "zeer zerr I am robot beep beep" mechanical movement is comical and usually means a bad connection or poor programming.
Oh I agree that he should have a more fluid and natural movement to fit with modern times. I hated the fact that the human-looking robots in the third movie moved perfectly like humans while Robo still "roboted" around.
I still think it looks more like someone wearing a suit in the new movie though, which might make sense because he is still mostly intact and didn't actually die in the new movie!