Rob, I was thinking of going with the Rumbler for my SS It also sounded great on Demonic's car when I heard it on Saturday. But I put the rumbler on hold for a minute when i seen this
I almost busted a nut when i seen and heard it in person at Atco.. It cost a little over a 1,000.00 and you have to drive to Long Island to Kooks shop to get it done. I may get one this summer.
Here is a video of the exhaust.
http://video.tinypic.com/player.php?v=4dnh9bd