One thing Yamaha has over the other makes is XG. This is Yamaha's extension to MIDI. With the later keyboards (PSR740, 2000 and above) you have access to a very powerful synth, similar to an MU80 but with more effects, or an MU100 with fewer voices. With one of the XG editors available or XGworks to drive it you are way ahead of the others. Much as I like playing keyboards by Technics or Korg, I wouldn't want to be without the power of XG.

Bryan