Hi John,
The S900 , is by far the best value for the money.
It has a ton of features , just about everything !!
I too have been looking or a new A/KB ,and have looked closely at the S900.
The only thing that is holding me back , are those rubber buttons.
However , NO TWO S900`s will be the same , that is a certainty. I have had a chance now to try a couple and both were different , mainly , the buttons.
The last one I tried was almost "A-OK" , but then I think to the first one I tried where the buttons had almost no feel and some even stuck.

I hope you get a great one , please be sure to post how it is , as far as build quality.
I`m not sure if it is because of first run jitters or just poor quality control.
The key bed on both were the same , they are not bad , but not like your KN`s , that is certain.
But like I and many others have said "it truly is the best buy right now" you can`t beat it for sound , it is amazing !
Anyway , best of luck , and keep us informed !!

Gary