I bought this used Yamaha KX61 on my right side here in the studio for $90 used some time ago and the keyboard quality is far, far better than the low end M-Audio. It of course depends if you try to avoid doing anything bad with less quality keyboards, such as avoid transporting them or otherwise moving them, having a cat jumping around in the studio, kids banging on the keys and so on…
Another good used brand is Edirol or Cakewalk (than then became Roland and they hiked up the prices for the controllers quite a lot). These keyboards feel very similar to the early eighties synthesize keyboards (Jupiter/Prophets.) . What I’ve also have done is to recycle old keyboards I don’t use that much as controllers, just using the MIDI port into the audio interface/DAW. So that’s another option.
Anyway, every keyboard player has their own ideas of how the keyboard should feel, weighted, semi-weighted, light. I myself prefer light keyboards as I’ve heard stories of accomplished keyboard players getting hand problems due to weighted keys (such as pianos.)
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