In the current class of new cars, I think Mercedes Benz might have the edge in reliability. However they are both german cars, have too many parts that CAN and will fail and some of these are beyond MB or BMW's control. That being said, I read that the current C-class was heavily tested before its introductions http://emercedesbenz.com/Jan07/09_Ov...C_Class_1.html I doubt BMW did that with the e90 or F30.
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