Well, the S-Type will be a bit quieter than your current Solo MR400/MACH46 4" System, but it's still a good bit louder than stock, though drone is pretty low, even after some drive time. That being said, a more cost-effective solution would be to see if a local exhaust shop could cut and weld in an additional resonator to quiet your Solo kit down a bit, though the S-Type kit is still a good choice.