I'm a professional composer looking for a weighted-key synth that's 1) a pleasure to play for someone trained on piano, but 2) also has many synth sounds and capabilities. One feature I absolutely require is to be able to get out of equal temperament when I want to --- for example, to be able to play in just intonation, or in Mideastern or Indian modes, ragas, maqams, etc.(This can be done either by means of pre-programmed modes, and/or by simply changing the cents of the intervals manually... ideal is to have both). I've been considering the S90 XS, but no one's been able to tell me whether it has that feature (as did the old Korg M-1, for example, though in that feature it was rather crudely programmed). Can anyone tell me whether the S90 (or other weighted-key synths) enables the user to get beyond equal temperament? Many thanks in advance for your help and suggestions ... oh yes, another thing, though not as major: ideally, I'd like to have an instrument that somehow combines weighted keys with typical synth key-sensitivity, though I've never yet encountered such a creature.