sure, I have and argument, yes the Rs6 is faster I never said it wasn't.It has more power so it will obviously be faster, whats stopping BMW from putting a 600 hp engine in a car?nothing except that BMW balanced all dynamic elements of there cars better. and yeah I saw the other test it was 4 sec behind over a larger track with more straight aways where any car with big power will dominate.Anyway when you consider that the M5 is how many years old and still is more technologically advanced(engine, 2 international engine of the year awards). I have also seen numerous tests where the M5 was around .5sec slower to 150mph then the RS6 which is nothing and is very impressive, and the M5 is faster from 50 to 70mph, thanks to its brilliant engine. Also the M5 is hundreds of pounds lighter then the porky Audi, which means is more nimble, and when you factor in the rwd the M5 is the default choice for a car and driving enthusiast like me. So ill take the M5 b/c its more driver oriented, more enjoyable to drive, and still fast as heck. And you can have you RS6, I could care less if its faster...there more to a car then that.