Truth is, most of the low milage F10 M5's (under 5,000 miles) you see for sale are actually dealership owned cars that the dealership used themselves and are now selling.
Even my own dealership here in San Diego admitted to this. We have Dealership Service Managers, Sales Managers, Regional Managers, and even the Dealership Owners themselves that use their dealership bought F10 M5 as their personal car for a few months and then dump it. Sometimes they get hooned, other times they don't.
It may be good for a potential buyer because they now get an almost new F10 M5 that already took the intitial depreciation hit and don't have to pay the destination fee or gas guzzler tax. On the other hand, you never know exactly how the car was driven by the dealership owner. I've personally seen dealer cars hooned before and even heard one story of an F10 M5 with like less than a 100 miles on it that had already been in an accident, with the dealership claiming that it got hit by a deer or something and was on sale for low 90's.
Currently saving my pennies for the 911-Fighter. The McLaren P13 500S.