I suppose you have your reasons, but I,as well as others, don't think you get that much more over the S910. I saw two on the Yamaha forum that had S910s, bought S950s only to sell them and bought S910s again.
Then again, some love their S950s.
Good luck
Bernie
That's wierd, I don't see how someone could really prefere a 910 over 950. 950 has a better VH, Drums and some new new sounds and styles. I think it's a good move up. But if you are tired of the Yamaha sound there's a few other choices at that price point.