I just installed my Cobb SRI and I don't find it loud at all, it's very quiet in low rpm and gets louder as I get on the throttle . I also thought I was going to be able to hear the stock bpv more than I could, it was also fairly quiet, hopefully that will change when my Forge bpv gets here next week. Overall it's a very nice piece and install wasn't bad at all except the mounting bracket holes didn't line up with the holes on the MAF housing very well so I had to drill a new hole but no big deal, this was my first time modding a car's engine and had no problems with the install.