The car is an absolute joy to own/drive. Many people who ride in it can't believe that it is "only a V6." I tested this against the M3 and honestly it just came down to the extra 2 doors. You couldn't go wrong with either one.
The engine is just unreal. It won't blow you away but it will always put a smile on your face. Also I found the handling and comfort levels to be very good.
The stereo is a little weak for this type of vehicle and they seemed to have addressed that with the C55. But overall, there are very few complaints about this car.