I love my Audi S4, but after taking it to a track last year, I quickly realized that the stock brakes, while great for road use, were not going to last for long on a track. I did a good deal of research before deciding on the Stasis 370mm brake kit. My new Stasis brakes are outstanding. The brake feel is much improved over stock - Its much easier to dial in just the right amout of braking. The kit looks great, too. It stands out without being too flashy or "over the top". I would recommend the Stasis brake kit to any S4 owner, as the improvement over the stock system is significant.