In an earlier post I asked for opinions concerning the effectivenes of the insert cones. Except for one negative opinion involving their use at the collector location, I did not get much useable feedback. Since Sean and the tech at Dynatech suggested that I try inserting them in the very end of the tailpipe, I decided to try it. The purpose was to reduce the harshness of the sound slightly; reduce the intensity of the sound from across the street ( kindness to neighbor gesture) and make the sound a little more throaty. Today I had them put in and spot welded in place. I have a Corsa cat back and the open end of the cones is now about four inches in from the edge of the exhaust tips. The difference is subtle but it is present. My wife noticed it immediately. I tested the car tonight and there is no noticeable effect on power. So, if some of you with a supercharger are looking for a little subtle noise abatement, I think that the cones work.