Depends on the car and situation imo. Something like that, where anyone could've bid, and its not really that special, go for gold on making a profit. But it sucks when someone looking to make a buck (ie: a car dealer) on an uncommon car snipes out legit people that would own and enjoy the car, just to flick it on for more and put it out of the grasp of the people that actually want it. Even worse when they decide they can make more money selling it out of the country instead, too.
I like the look of the F10 M5, especially in white. There is one i see locally that gets regularly fanged, and have seen it drag people off at the lights before, and it looks and sounds great. I'd skip the shitbox (flamesuit on; its ugly, sounds bad and unreliable) that was the E60 and save/wait for the F10 to depreciate into grasp.