Sorry to ruin the party but ...
altough Tyros and/or Genesys are indded an improvement, they are NOT realworld sounding at all. Synth(etic) feeling all over.
My personal fata morgana of Gigastudio-type quality sounds combined with sophisticated auto-acompaniment styles still remains;
I fear there is no alternative than to use harddisk streaming and NOT limited chip-based sounds.
listen to "A little Chopin" at
http://artists.mp3s.com/artists/42/john_lewis_grant.html This is a streaming sampled piano.
Imagine a Tyros build with this level of quality...
Aahh imagine....