You can really tell the XBOX controller wasn't meant for DDR. It buttons are on a slant and they don't flow as well as the PS2/PSX controller does.
If you're playing UltraMix or UM2, don't use the controller, get a dance pad.
I can see how playing on a keyboard feels good, but I really don't like it. Although it's an alternative to DDR on console/arcade if you don't have it.
Yes, the XBox controller is awful. I play on both dance pad and keyboard (keyboard whenever I'm too tired to actually move/not allowed to use the pad/am at school), and I enjoy it as much on both. I used to play Flash Flash Revolution before my first pad experience, but it wasn't as fun back then. I guess I associate those arrows and that familiar music with the fun I usually have when playing DS Unleashed, and it kinda gets fun just because of that.
Plus, DWI lets me play all those songs I hear everybody talking about but would NEVER get a chance to hear/play otherwise. It's good practice for reading arrows, and it's also fun to move to those arrows even if you don't have an actual pad under your feet. Like I did on Non-stop mode today... damn, if I was on an actual pad, I would've failed instantly... it's tough. Especially when you get two PARANOiAs in a row, followed by MAX. (period) on standard...
Speaking of keyboard... Not an AAA, but still felt amazingly good, especially considering my best score last week... a C that was, through pure luck... But lookie now!
It explains which ones are the most compatible and stuff. I ordered the second one down, becuase the first one was out of stock. It should still be compatible with my pad though.