I've always felt (since going from the Roland S-760) that the anti aliasing filter sounds worse in the EXS than Kontakt. Did you do the test playing the sound at the root key or did you pitch it up/down from the original?
It's an easy test that I could conduct myself, not just right now as I had a few drinks.
(If I remember

I'll promise to post an octave +- test review tomorrow.
Jens
PS. Science is science and can't be argued with. So I guess you're right.