Go try it out in the store first. I played the M-audio, and the action was terrible; too heavy and sluggish. Its only like $400 so you get what you pay for.
I suggest a yamaha Mo8
Yep, thats the problem with inexpensive hammer action or weighted keyboards...very sluggish action. The keys are usually too heavy and clunky and they make a "clunk" noise when you hit them down. You gotta be ready to dish out money for a good wighted keyboard or digital piano.
If you decide to go the digital piano route, be ready to spend money on an amp setup. The in-built speakers are usually horrible!!
If you go the keyboard route and you have money to spare, go the Mo8 round or the Fantom X8.