I downloaded Rikkisbears collection and added the styles unique to the Genos. It's a definitive collection.
You know, I haven't done my first gig yet with the SX900. I'm waiting for my second SX900 to arrive. As far as the assignable buttons, I plan on using Talk On/Off, Fade out perhaps, half fill on/off.
I use a MIDI activated footswitch so I use one pedal to activate the vocal harmonizer, one pedal for sustain, and one for fill to self. It's an amazing keyboard!