"I upgraded to the SX900 because I’m a sucker for the latest model. I assume, rightly or wrongly, that a new model will sound better and have advanced features from the previous one. Among the PSR's, I’ve had the 910, 950, 970, and 975. Keeping the latter as a backup. The one fly in the ointment was the Korg PA 1000. Traded it pronto. Just couldn’t adapt to Korg. My initial comments may have been premature, since I’m warming to the SX900. Still can’t get the VH to work properly. In fact, it’s so bad, it’s not usable at the moment. Everything else is super. Reading the manual might be a good option. A 7-day wait before commenting might have been better. However, I’m prone to poke and hope. That concert piano voice is coming around. It takes some tinkering, but my hearing is adapting. If anyone is straddling the fence about the SX900, give it a go. I don’t think you’ll be disappointed, especially if you play one of the earlier PSR models."
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"I’ve owned all the keyboard that you mentioned and I have come to the same opinion as you, this sx900 does grow on you, I like everything about it apart from the black gloss facia, (the 950/975 facia was Matt black, I never had a headache playing a keyboard before, where I work is low lighting so I need my keyboard light).
Nonetheless, I will say that it’s the best PSR to date.
Can’t comment on the VH, I have VL2 and VL touch, will stay with them.But The sound department hasn’t changed a lot apart from the scat voices which are pleasant enough,
I have re-tuned some of my registrations etc, new voices, FX etc,
And re-recorded some of my gig songs again on the SX.
This is my experience after 2 weeks, apart from adding some of the scat voices.My new re-recorded songs sound almost identical to my S910, not a huge difference.That’s just saying how good the voices have been since the 3000,I will upload some songs as soon as I have the time to join the audio."
source: Psr Tutorial Forum