I have owned an M-5 for about 6 months now. I can say, I cannot go back to an "ordinary" BMW. The car is the most fun thing one can do with shoes on. It does drive a bit jerky at slow speeds, but I will say, it was not meant to go at slow speeds!. On a serios note, the SMG takes a little bit getting used to. I find manual to be a lot smoother. The only down side it gas milage, I am aroung 14.6-15 mpg. But it makes a statement, and turns heads whereever it goes. I love the growl it makes when I downshift. For all the folks who want an M experience, once you drive one, you cannot go back!
I have now owned the M5 for 4 months and it is pretty much broken in. I love it! I told myself min miles ~6-8k a year, but I have to drive it everyday! I just get a big smile on my face every time I get into it! Gas mileage update - I have a 25 mile drive to work everyday on a 45mph road w/ about 30 stop lights (that I constantly get caught at). I mostly drive in 400 hp (D1), but I let the 500hp monster go quite frequently (S4)- say 5 times a day (I'm gonna need new tires soon $$). With that, my avg gas mileage is better than when I first got it (see my first review) - 17mpg or ~330-350 miles before I fill it up.
Have owned for 2 yrs now and I still love it. Gas mileage has settled down ~15mpg. I took it in for a checkup ~16k mls; got a 328 loaner. Wow, there is a massive difference. I am completely and forever spoiled by my M. Had to buy new rear tires after 1yr/10k mls=$850. My fault-too much M button w/ traction control off. My only dislike; it is too much car for my streets. Almost unusably fast- no chance to really see what she can do!
This car is absolutely amazing, but this car will take most people a little time to learn how to drive. For example, on an up-hill start, the transmission has a built-brake that prevents the car from rolling back until accelerating forward, and resetting the clutch helps eliminate the jerky shifts. Once the car is learned, allow at least a month, it is an absolute masterpiece. If you want a car to just jump into like most traditional auto sports sedan, this car may not be for you. If you are willing to put a little time into learning this car, it will satisfy you every driving need! Take the driving class!