When it comes to high-performance, high-power, big-body cars, the BMW M5 is king. The latest F90 M5 is the best M5 ever, but there is always room for improvement, even on something that many might consider perfection. If you want a high-end exhaust for your high-end M5, Remus is a very good option. Just recently they came out with a new cat-back and axle-back for M5.
BMW did a pretty decent job with the stock exhaust, but they left a little bit on the table. By increasing the diameter of the piping from 80 to 84mm, Remus was able to get a little bit of power out of the F90 M5, but more importantly, give it that sound that F90 owners want. The catback and axle-back are available separately, and they will be available with either stainless steel or carbon fiber tips.