A great idea Bill...main things missing would be those awesome SA Voices (as weell as Yamaha's exclusive Mega Voices), Audio Recording, Audio Drums, and Vocal Harmonizer (VH-2 on S950).

Plus, carrying two keyboards to gigs would be a bit of extra work, as well as the complexity...also the sound would be Korg based so it would tend to sound similar. It would be the same type similarity if one used a Yamaha PSR-S9** series and a Yamaha MOX6.

I think John Smies idea of PA-500 and PSR-S900, and/or a PA-600 and a PSR-S910,(both PSR's have Audio Recording), the latter pair being a tad better in my opinion, is very good as well. Plus, the player would have two completely different tone generators and two contrasting style engines.

Otherwise, the PA-600 and Krome sound like a nice economical match.

Of course, it all depends on the user's needs and playing style, and type of music being played.

Ian