I raced an E39 M5 in my BPU Supra from 50-120 and there was maybe 1 car length in it, if that.
It's international, and the best site for all your M5 needs.
Big, much bigger than the on paper figures might suggest. The E46 M3 is a very quick car, no two ways about it - sub-5 seconds to 60 isn't hanging about.
I love the E39 M5 and would dearly love one, especially now that the cheapest cars, not even mega mileage examples, are down to £7k. The only thing that would put me off are the running costs. My editor was lucky enough to run one for just over a year as a company car recently and the total running costs for 22,000 miles, not including fuel, depreciation, insurance, Tax or MOT, came to £8500. Fuel, incidentally, came to £5500...