I've seen my car vary as much as 30bhp on different rollers with the same spec. This along with the fact that when my car was doing 170bhp I could quite easily keep up with most so called 200bhp cars.

I simply think 200 BHP is the magic number for RS Turbo owners, the same way that 500 BHP is the magic number for Cossie owners, its amazing how everyone and their grandmother has cars with this sort of power on a mass produced performance chip but for some reason they usually have issues on rolling road shoot outs in magazines

If you car can do 200 bhp it should do it anywhere not just specific rollers imho