I have a couple of M-Audio MIDI keyboards right now. The M-Audio Keystation 61:
[VIDEO]http://www.amazon.com/M-Audio-Keystation-61es-61-Key-Keyboard/dp/B0002H0GF0]Amazon.com: M-Audio Keystation 61es 61-Key Keyboard: Musical Instruments[/VIDEO]
And the Oxygen 25, that I really just use as a remote control for reaper:
[VIDEO]http://www.amazon.com/M-Audio-Oxygen-25-25-Key-Controller/dp/B002VYJDYW/ref=sr_1_1?s=musical-instruments&ie=UTF8&qid=1311361125&sr=1-1]Amazon.com: M-Audio Oxygen 25 25-Key USB MIDI Controller: Musical Instruments[/VIDEO]
They both do what I want them to do for the most part - I use the big one for actual synth stuff, and the small one like I said, as a remote so that I can adjust levels and have a start/stop/record button separate from my keyboard.
I'm leaning towards picking up Trilian, and neither of these really do note accuracy very well. What I mean is, there's a definite "on" position when you hit the key, and while they're somewhat velocity sensitive, it's not good enough for tracking an actual VST instrument.
I don't need anything huge, something like two octaves would be fine, but I want something that's super accurate, so that it can pick up minute differences in how hard/soft I'm hitting the keys.
What's good? $500-600 or so.
I have the axiom 25 and it does everything that i need it to do, and more.