QuasiUnaFantasia
I have yet to comment in PW on your contribution (it will happen though), but there I am unlikely to comment on the piano sound in itself. However, listening to it now (very well played, by the way) I agree completely with the "singing tone" comments. In my view the stand-out feature of this sound is a long sustain which does not drop off in volume rapidly, unlike so many sampled piano's out there.
But, my personal experience with Pianoteq is that I get "ear fatigue" after a while, and I'm speculating that the reason for this is exactly that long sustain at high volume. This idea just came to me now, so it has not had time to be fully examined yet.