Well I installed the Dynomax 2.5 inch exhaust catbacks about 2 weeks ago...instaklling it was a pain from the ground....multiple jack stands floor jacks and 2x4's were used to get the car high enough off the diff. As for the sound I really enjoy it, not loud but noticeable, nice and deep especially at idle. Give it some gas and it sounds mean but not loud, exactly what I was looking for. Dont want to attract too much attention or law enforcement. I have notived good gains as well, I was quite surprised. I will keep these on here for a while until I get a little more in the guts of the car. Thanks for the input you guys gave me. Great system for the price too!!!