My B58 (downpipe, Muffler delete) sounds pretty damn sexy to me. I love a V8 (especially the e9x) but the sound of my modded B58 is just way too unique. I get compliments all the time.
As for the best, S85 is definitely up there..but have you heard a supercharged one? There's no competition at that point, that exhaust is literally the antichrist.
For example: