I purchased this exhaust to replace my Invidia r400 system. The old system was a bit loud for my tastes so I decided to give the HKS unit a try. The exhaust construction is fantastic and the tone is even better. It's just a little bit louder than stock at both idle and full throttle and has a nice tone that accentuates the engine noise perfectly. If you are looking for something on the quieter side, this exhaust is definitely for you.