[heavyD^2]

I don't know about that. I feel the rear door transition to the fender is nearly identical on both cars with G80 having more of a pronounced rear fender bulge like the M2 while the F80 rear fenders are more flared being the only major difference of note. IMO it comes down to personal preference between the F87 and F80 rear fender implementation. I like them both and feel the F80 flare is more subtle while the G80 bulge stands out more against its regular 3 series brother.