I haven't played many FPS games on the 360, but one thing I noticed with Bioshock is that it is a lot more forgiving. There is a lot of slop you can do in your aiming and it still counts as a hit. I assume most DA controllers are like this. Sure if you don't actually have to aim as tightly with a DA, then they can be competitive. DA players must just be used to sloppy aim assisted controls. The shotgun and obviosly some of the explosive weapons you can be sloppy with in the Conduit... but not normal human guns.
I find it funny how some people forget the wii controllers also have buttons. 








