The smallest four-door Mercedes coupe may not have shown a single wrinkle, but last year it received its mandatory facelift, featuring redesigned bumpers and LED lights, and an upgraded interior. The desirable shape and many impressive details have remained, but so has the somewhat family-unfriendly size. We tested the beauty queen of compact cars, manufactured in Kecskemét, Hungary, with a respectable-sized turbocharged petrol engine supported by a mild-hybrid system.