I really like the solo instruments better on the KOrg (tough i dislike both piano's but i must be spoiled by my true piano's vst) but the Korg sax is really good..
And even tough the Korg has awesome Guitars, i prefer the styles of the Audya, they just cut straight true it....
This supports my feeling that using an Audya 4 module and VSt's for the solo instruments could be my next setup.