the keybed alone on the Tryos 3 and the fact that the keys are larger and longer makes it a no brainer for me.

The keyfeel of the Tyros makes the overall playing experience much more enjoyable and authentic over the PSR. Its also much more expressive as you have more depth in the keys when u press them, where as on the S950 they are short, spongy and shallow...

The Tyros also has the Master compressor which is not in the S950 - if that makes any difference to you as well? not a big deal for most folks though..

I have owned so many PSR's over the years (PSR 1000, 3000, S910, S950) and they always leave me begging for more and feeling somewhat "empty".

Good Luck
Nick