My favorite instrument sounds on the PSR-S900 (and Tyros3) are the SA Sax, and the SA Concert Guitar.

They respond exceptionally well to legato playing, and the Sax even switches from poly to mono, automatically...playing legato also removes the attack on subsequent notes, adding to realism.

Am I going to fool anyone, especially someone who plays guitar or sax?

Nope, probably not, but 90% of the listeners really don't care...they think it sounds great...and I enjoy having those extra colors to add variety.

Ian