If you can tell the difference between 192kbps and 320kbps in a blind test, I would say that is impressive.

I'm a musician and I have a few "audiophile" friends that say they can tell the difference, but when we conducted a blind test, they were basically just guessing.

I am not saying it's impossible, but there aren't many people that can hear the difference, I know I can't. Even with my Grado cans.