No difference at all.

Still fails DPC test and audio/video still lag every so often.
Looks like it's a 2 month old driver (12/29/2008) which is older than what Windows Update offers (1/13/2009)? Correct driver uploaded?
Back to driver from Windows Update. And yes Windows update offers latest version (1/13/2009) again after installing this beta driver, so it to believes this beta driver is old as well.