tawheed
I have the FVD sound muffler you are considering, and I love it. I don't have a sound clip, and my car is a 2.7, but it is just what I was looking for.
I had done the 'crios mod' for a little more sound and I liked it, but it just made me want more.

I didn't want the drone that many systems seem to have from reading other posts, and I liked the dual 3.5" SS tips versus my OEM non-S single tip. Any claimed power increase would be icing on the cake.
I worked with Rhonda, and she got me a lower price than what is listed on the link, and the service was great. She sent me a short clip, but the car also had their headers and/or bypass pipes so it was not a direct comparison. I installed it myself, and it was an easy Saturday job.
Good luck with your decision.