The BMW M4 is getting a lot of publicity these days. And the number of aftermarket companies that have come out of the woodwork to build programs for the new sports coupe are certainly helping build upon its popularity. Some programs are more comprehensive than others, but the point is simple; the M4 is getting a lot of love. Vorsteiner’s the latest company to take a stab at the M4. The German tuner didn’t build a kit that’s as complete as its contemporaries, but it did manage to effectively create one that improves the car’s credentials.