My wife and I apparently have only the second unit with the Upsampler. We've had the player for just a day--not much time, clearly--but thus far we prefer it with the Upsampler 'off' more than we do 'on'.
What we've noticed so far:
Upsampler ON:
The music sounds more blended
Softer edges between the instruments
Midrange feels slightly more airy
Upsampler OFF:
Better clarity
Images clearly focused
Distinct separation of instruments
I know that the choice between the two will be a personal one, and we could certainly feel differently as the player breaks in. Depends on the specific song as well as to whether or not we prefer one effect or the other. I will say that right out of the box, the player itself is ridiculously good. I know that's an odd way to put it, but those are the best words I can find for something that plays this well.
