Eek, okay thanks. If it can't play GM MIDI then I'd presumably have to use wav, which could work but might be tricky. Re the PX-5S, I notice that Tim rates this highly on his site. However, its in the same sort of price range as the console Casios we'd been talking about I think. Its got extra features but mostly the features seemed related to use on stage. So maybe its not what I need either. Which brings me back to the 780, 850 or Kawai cu34, depending on what balance of features and price I want. One other thing I liked about stage pianos though is that the stand is separate. In the past I've seen mdf wardrobes disintegrate over time. Does that happen with the sort of material used for the 780 and 850 over time? Also, what sort of MIDI files can the PX-850 play? Thanks again.