I have had my 4 door M3 since 2003. I bought it from a private dealership with only 17K miles on it. I added the Dinan software one day at the dealership on a whim and wow 155 mph and I had to stop. It might have done 160, but who knows, I could also have gone to jail because of that. Used it as a daily drive until 2007. Now it is strictly for weekends and appointments. I have a truck for daily use now. Now have 107K miles. Normal maintenance and no major problems thus far. I could keep this car forever. My 9 year old son loves it and wants me to keep it for him when he gets 16. Yeah right!
Quick and handles great. Great gas mileage on highway (29 mpg). Try and get that out of a 0-60 car in under 6 sec. Harmon Kardon sound system not bad for stock. Lot's of fun to drive. Just beat Ford Mustang GT in race from signal light. You should have seen their eyes when I waved goodbye.
Cup holders too small. As others noted problems with tail light bulbs. Just change the fitting and that will fix the problem. Don't change the whole assy like the dealership wants. A/C could be better. Boy does it goes through tires. Wished the seats were automatic. Too many manual adjustments