OK, I have been evaluating for a while now....Have not played or heard a PA3 LIVE yet...but,
This is one reason I am going for the T4...
Use good speakers, turn it up LOUD and just listen to the different orchestral voices etc...the clarity, the fact that you can pick out individual instruments...and they sound right together.

http://www.youtube.com/watch?v=bIqFE1sluxI&feature=fvwrel