The 360 controller has come to be my favorite (though i have yet to touch the ps3 one), though I would prefer that they flatten the tops of the buttons a bit so they don't hurt my fingers during long play sessions where you might be aggressively pressing them. The dpad gets the job done too, though I do like the playstation style d pad a lot.
The 360 controller's dpad is awful - probably the worst I've ever used. Any 2D game (fighters especially) aren't playable with the default controller due to the dpad. I tried playing Street Fighter II Turbo HD Remix with the controller, and I just couldn't do it.