I wouldn't say the S900 sounds better than the Tyros3, but I like it better for gigging, and the sounds are excellent.
Using an MOTL arranger isn't what it used to be years ago...they now rival the TOTL instruments.
Ian
_________________________
Yamaha Tyros4, Yamaha MS-60S Powered Monitors(2), Yamaha CS-01, Yamaha TQ-5, Yamaha PSR-S775.