At first I thought the volume of my Eisenmann Race was perfect, but then I noticed that at higher RPM's, the engine noise overpowered the exhaust and I couldn't hear it from the inside. Now I added the turner test pipes and the sound is perfect from the inside, but has more drone. If you are not sensitive to drone, go with the Eisenmann race...The drone never bothered me.
///M3 Mods: | Eisenmann Race Exhaust | Primary Cats Delete (TTP) | ESS Tune | 19" Advan RS | Eibach Springs | MS Air Filter | BMW Perf. Spoiler | BMW Perf. Splitters | Euro LCI Tail lights | Angel iBright v.3.0 | 20% Tint | Matte black Kidney Grills | CF Side Gills | Painted Reflectors | Black M3 emblem