Hmmmm ... compare the 3x to the 900, OK:
1) Key feel - comparable, edge to the 3x
2) Size/weight - edge to the 900 ... lighter AND has speakers
3) even as far as I remember - both fantastic.
4) TC - 3x is better, but now that I'm impedance matched, the 900 is a close second - better than Roland or Yamaha for sure.
(Fran ... don't even weigh in here - we know ... the G70 rocks)
5) screen seems for consistent on the 900 - maybe it's calibrated better, or just fresh and new - both great
6) recording - seems even here too.
The edges:
900 - price, speakers
3x - harmonizer, sliders, multiple outs, XLR mic in, (sampling?)
If the 900 had an XLR mic input, and dual outs - it'd be really hard to beat the value. It's hard to beat right now, IMHO.