I ain't sayin' it's the be all and end all but I know jack about controllers and when I bought my M-Audio Oxygen controller I just hooked it up, selected it in Sonar and it worked. No drivers, no fiddling around, no nothin'. It was dirt cheap too.
My Korg thingy? Not so much. That was an epic hassle.
However if you have a bit more cash and are looking at M-Audio gear the Axiom line are supposedly pretty slick too.