This seems a touchy question in a couple of other forums, and it seems that the keyboard players are generally somewhat divided on getting good live sound reproduction from keyboards. The major division in opinion is between "amps" versus "systems".
The "systems" guys seem to somewhat like Accugroove and JBL cabinets, where the "amp" guys talks about the Traynor and Motion Sound amps.
I had an old Peavey practice amp for years, and just in the past year got a Motion Sound KP200S stereo keyboard amp. I've had all kinds of different amps/speakers thru the years, and can say that the Motion Sound is abolutely the cleanest set-up I've owned. My clone organs sound especially good through the Motion Sound.
But, I also have to say I think of the KP200S as more of a stage monitor than a dedicated "amp", as it is only 100W X 2,. IF you play with a loud band and depend soley on your stage volumn from the amp, then the KP200S may be underpowered to cover the room. Still, it has 2 direct-outs built into the amp and if you're running your keys to the main PA it should work fine. Motion Sound
also now makes the KP500S (500 watts) which should be substantially louder.
I've not tried the Traynor amps so I can't offer any opinion.
BUt, I will offer that hearing my keyboards in stereo is much better to my ears on stage than any of the mono systems Ive ever used.
B3