ive just tried maesynth, its great, one issue is that if you play keys with very little timing in between them both, then some extra keys/notes usually play in between them for no reason! its more noticable if you turn the decay up to maximum, but it still happens with it off.

i know its early days yet for the program still being in development-its the best/only virtual n900 piano ive found yet would b nice with a wider range of keys to use too akin to the real thing-i can almost play axel f-aside from the extra notes playing, there just one of two keys missing to finish the song off, lol! great program