hmm..not sure about that! apart from the M badge this baby always look beefed up. Mufflers, side vents, body kits, rims.
I have the 530I with the sport package and every time I see the M5 it puts me to shame.
They do subtle addenda, one who knows can tell. For instance the only thing that seperates a E39 M Sport and the M5 are wheels, mirrors and quad tailpipes...the M Sport and M5 have the same front end...
The E34 M5 and reg M Sport, the diff was the badge and wheels, same for the E28...
The E60 550i with M Sport and the E60 line in general was more aggresive due to the styling, so therefore the E60 M5 would have been more aggressive, if you put both the new F10 M5 and the E60 together, you'll see that neither is more aggressive than the other---but, the newer one is more cohesive...