I've had a thing for the BMW 6-Series ever since "Spenser: for Hire" shared airtime with Mötley Crüe. While Robert Urich had a cool Mustang, Avery Brooks had a vehicle worthy of his icy-cold demeanor: a white BMW 635CSi. Could there ever be a better vehicle in which a man could do the right thing by any means necessary? There is now. The BMW M6 has tons of M-tuned street cred and many of the right moves. Many, but not all.