When BMW released the M4 back in 2014, it officially became the poster car for fans of the company’s M division. Two years later and the M4 has proven worthy of carrying that mantle for BMW. But let’s face it, a good car shouldn’t settle for good. Likewise, a better car shouldn’t stop there either, if it can be the best. Part of that responsibility lies with aftermarket tuners who make their bread by giving cars like the M4 the upgrades it needs to further stand out from the crowd.