Hey partylyk1999,
to the forums.
In a nutshell, check out
this thread about the A8 issue, it appears to be completely manageable. If you buy from a dealership, you can make sure they address the problem, and in fact you can use their handling of this as a test to find out which one will support you best in the future.
My A8 is tuned and the tune has shown it as the awesome and strong transmission it is, shifting smooth in tour mode and being a beast in sport/track, with near perfectly timed up and downshifts, the only snag is the relatively slow reaction time to paddle input.
With that said, you may want to give a strong consideration to the M6, it's a sturdy, very high quality Tremec TR-6060 unit with no lift shifting, and it would definitely give you an awesome driving experience.