I've heard quite a few cynical remarks about the available horsepower in the new S6 versus its weight, especially compared to the RS4. But here's the thing I just realised: RS4 engine is a 4.2 litre V-8 at its highest state of tune. The S6 has a V-10 quite possibly at its lowest state of tune. But hang on a second, isn't 400+ hbp is a lot of horses in any car? - who cares! You should easily be able to chip the S6 to coax 480-500 bhp out of it. I reckon new Rs6 will simply be a highly tuned version of the S6, with about 550 bhp, when it appears in 18 months time, so why not do it now by beefing-up an S6? What do you think?