I have had this car since 5-2011 and have now put 15,000 miles on it. It's solid, fits me like a glove, handles well, if not like a sports car and has all the bells and whistles I need. I added the luxury package, steering wheel, dynamic seating (a must have) and the P2 package. Fuel mileage has been almost 32 overall and 36-39 HWY. The DEF fluid is no big deal. Buy at most gas stations or car parts stores for $12 for 2.5gals. I think I have added 5 gals total (maybe 7.5). Big deal. M-B will scalp you if they put it in but it's simply filling a tank. Love the car and not one issue.
Dynamic seating, comfort, torque, styling. I don't know exactly what it is with the styling but as soon as I saw this car I knew I wanted one. I'm not sure why but the package just seems to work. It's sexy, stodgy, cool...
Bigger wheels. The 17in wheels look 1 or 2 inches too small.