Sorry to disagree guys, but I was told by someone who has DEMOED the BK9, that he felt the keybed was similar to (if not the same as) the BK5..

And looking closely at those images above, the keys on the BK9 seem a little shorter that the JS...btw I played the JS, and the keybed is not that good you know, very short key travel which felt quite odd for piano parts....

D