George,

The 9000Pro's Live Grand Piano seems to be sampled from a Yamaha Grand. The SD1's Grand Piano is a European Grand with darker & richer tone. The lower end also is richer & deeper. I'm using a pair of studio reference monitor speakers and I can hear subtle differences. Sound is very subjective though, it also depends on the EQ and effects. In general the SD1's presets have more effects than 9000Pro's presets.

Henry