In my opinion, the Roland BK-9 has a more "live" sound. It also sounds like a more serious instrument. In comparison, the Yamaha PSR-S950 sometimes sounds more "toyish". I base my opinion not only on the above video, but also on hands-on experience in stores.

I always thought I'd get either a Tyros or a PSR-S950. However, lately I've been hearing lots of online demos, and I'm not so sure anymore. Don't get me wrong, the PSR-S950 sounds good, even very good, depending on the voices and styles chosen. And the intros and endings are the best I've heard. The BK-9, however, has a certain "transparency" in its sound that I like very much. It reminds me of my Yamaha Motif XF6. You can hear each instrument very clearly, cleanly and distinctly.

There are other factors which, for me, are important, like better (and more) keys on the BK-9. The PSR-S950's keys give it a toyish feeling.

The acoustic guitars are not good and realistic on the BK-9, at least to my ears. Styles which contain them don't sound good. The BK-7m acoustic sounds are similar, unfortunately.

Right hand sounds may be better on the PSR-S950, except some of the SuperNatural sounds found on the BK-9.

Then, there's the matter of price. Retail prices are $1,900 for the PSR-S950, and $2,500 for the BK-9. Lately, the Bk-9 went down in price by $250, so that might lean in its favor.

On a personal note, I've also been comparing the Korg PA900. I like it, too. Hard to say which I'd prefer, without more time spent playing them in person. Any feedback would be greatly appreciated from those who've owned at least two of the above models.

Thank you, Donny, for starting this interesting thread.

P.S. Of course, there's also the new Ketron SD7 and the upcoming PSR-S970.....when will it end? I hope never!