..there are tens of thousands of styles available for download...
-that shouldn't influence your decision. As
Graham mentioned, most of these are duplicates or slightly modified styles circulating on internet all the time. When I got my first Yamaha, I too started to
collect them... separated good and bad ones, sorted them in categories... But when I needed a style for some particular song and searched trough them again, I usually found nothing
good enough. What a waste of time (at least in my case).
...My question is, how do these styles sound when played on the high-end Genos? Given the superior sound quality and capabilities of the Genos, would these styles sound significantly better compared to when they are played on other Yamaha keyboards?..
As
Mike said, there's no difference (except maybe in keyboard owner imagination). Yes, we can replace voices in style, so they sound more to our liking, but that doesn't really change the style (the accompaniment). What I'm saying is, for example, a good bass guitar player or drummer doesn't necessary need the most expensive instrument: how he plays matters -not on what he plays.
In short, if some style is really well made, then it doesn't matter much on what keyboard is being used. Because if needed, we can make final style sound adjustments to our liking anyway.
So, if that's your only decision factor, then I join
Divemaster's advice: you save a lot of money by deciding for SX700/900 and that money can be well spent for good audio (amplifier/loudspeaker) system -and that does make a difference.
Bogdan