you can't go wrong with any of the m-audio axiom series. best bang for buck controller i've ever owned. build quality rocks, keys feel great, drum pads, knobs. the 25 key version is under 200 bucks.
I've got an AKAI MPK 49, which I just love...I've mapped the faders and pots via midi to the mixer...has MPC drumpads (the real mcKoy)..built in arpeggiator, transport contrl...the keys took me a bit to get used to but I love 'em now....with aftertouch...I really recommend it!