I recently purchased a 2015 A8L 4.0T (after having a 2013 A8 W12 for a year). I really love this car, but the idea of all the gains from an ECU tune are exciting.

I did a Eurocharged tune on a 2008 MB E55 AMG a few years ago, and it made a HUGE difference on power and overall performance... but that car was out of warranty and so there was no concern about a dealer having issues.

Any input or thoughts about various tunes? I am considering the APR tune right now, but would love to hear options as well.