I think the original X-box controller is by far the worst of the recent consoles. It's far (far far far) too large, the back buttons are sticky and the X Y A B buttons just don't press as nicely as you'd like. Contrasting it to the simply pressed huge A / smaller B of a Gamecube controller, which for me felt very intuitive for simple games (A is your main attack or similar function, B is alternate), it seems silly of them to release a controller like that with all of that money backing the production of aforesaid device.
The PS analogue is probably the worst out of the lot, but the bumpers and main buttons are great. It still lacks in D-Pad quality for me, but then so do most of the controllers.