Regardless of hp claims, APR is one of the best tunes out there for the RS6. I had it on my other RS6 and its a rocket, with excellent data logs. The problem with it is that its waaaay too much money. I believe they still want almost 3k for the ECU/TCU combo. With time has come competition in the pricing. I particularly liked the different modes, and the ability to do throttle body adaptation. No one to this day offers that. I still when with Viper on my current rs6. Much better pricing, and you get all of what makes APR great, without the TB adaptation, and selectable modes. Also without the high price.

Quote Originally Posted by formula1man View Post
I have MTM for both the ECU and TCU, great but the ECU is very expensive compared to the rest. I would use whoever (listed above) that can provide real numbers (not ARP, etc) who's are a little exaggerated. I would also focus on the intake so the beast can inhale efficiently also. I have Dahlback racing intake which is really great, but pricey.
Best of luck with your search.