I understand the new seal is just made of 'Viton'....which the VAG was using for other applications like pedal bushings way back in the 80s. But I do not have any infomation that points to anything else being 'improved' on the superceeded TCs.
I have an ACES TC waiting to go in mine...I did get a code last year after a year+ of driving it from 78K. I felt some slippage once in a while but never a CEL. I cleared the code back last fall...scanned it last week and no TC code now and I can't really feel any slippage either. But I'm still throwing the ACES TC in soon as everyone I heard from says it really makes a nice 'upgrade' over the stock unit. I'm at 92K now. Pretty sure my TC is the one from new too.
SOLD ! 2003 RS6 Mugello/Silver -MTM
2001 allroad 6-speed (300K+), 1992 Mercedes-Benz 500E, 2007 Mercedes-Benz CLK63, 2010 BMW X3, 1986 16V Scirocco, 2005 Mercedes E55 Wagon