The "Velocity Garage" guy, AKA 'the Car Ninja', said, "If you MUST make the mistake of buying a BMW at least get a six cylinder." There was no punchline. He was dead serious.
That generation of 5/6 series vehicles (F06/F10/F11/F12/F13) lie 'in the next generation' of cars from the Crossfire. 8spd trans, variable valve timing, stop/start, on-screen nav., etc. Although I like 2000's tech I do try to own cars that don't yet have a parts-supply problem! Ever since the 2nd vehicle in/of my life-time I've NEVER BOUGHT A CAR WHEN I NEEDED A CAR. People think I'm a little strange doing things that way, but it makes car-shopping enjoyable instead of stressful and I always end up with a vehicle I really like instead of feeling that I settled for something. I bought the Xfire 1 month before my pickup got a significant leak in the front-engine cover requiring it to live on a steady diet of Bars Leaks, and although it still will sally-forth on every rainy day (keeping the Xfire eternally clean!) I don't trust it enough to go out of town in, which means I am beginning my search for a true equal-partner for the Xfire. I'm a sucker for "fancy-schmancy" interiors (hence my purchase of a 'tuxedo' Xfire), and 'your' generation of 6-series has some truly outstanding 2-tone all-leather interiors, but I'll only be considering 640's and NOT any BMW V8s, thank you very much! You know the ENGINE difference between a 535i & a 640i? .6 bar VS .8 bar of boost. Yep.