Brian,
There wasn't a lot of difference in the sound of those pianos and I would be happy with any of them. But to me, the most important part of playing a piano is having a 'loud' pedal, as I used to call it.
From Wikipedia:
A sustain pedal or sustaining pedal (also called damper pedal, loud pedal, or open pedal) is the most commonly used pedal in a modern piano. It is typically the rightmost of two or three pedals. When pressed, the sustain pedal "sustains" all the damped strings on the piano by moving all the dampers away from the strings and allowing them to vibrate freely. All notes played will continue to sound until the vibration naturally ceases, or until the pedal is released.
This lets the pianist sustain notes which would otherwise be out of reach, for instance in accompanying chords - and accomplish legato passages (smoothly connected notes) which would have no possible fingering otherwise. Raising the sustain pedal also causes all the strings to vibrate sympathetically with whichever notes are being played, which greatly enriches the piano's tone.
How to use the sustain pedal is the essence of playing the piano, and without it you may have a 'piano sound' but not a piano you can play 'as a piano'. And that for me is the problem. On my AR I do have a nice sounding piano, and I can adjust the 'sustain' on it (how long the note 'holds') but this is not the same as what you get when you use the loud pedal on a real piano. And that last comment in the Wikipedia description above, the vibrating of other strings in sympathy with whichever notes are being played, will tell you that the piano is a very difficult instrument to replicate electronically. This vibrating of other strings will cease as soon as you take your foot off the 'loud' pedal and the piano will sound different in this mode.
Listening to the above YouTube DEMO it seems to me that he has just increased the 'sustain' of the notes in general and all the notes he plays just run one into the other. Sounds a bit 'messy' to me. This is
not how a piano really sounds.
Hugh