The biggest difference between our two systems other than where the muffler is located is the overall sound difference.

Our cat back ( with the muffler at the back) has a deep mellow note that really never gets "too loud" when your driving, if your wheelin and you start getting on it its plain to hear its not stock.

Here is a vid of this system for those that have not heard this system

http://www.youtube.com/watch?v=0th1aiaNXi4

The relocate system has a considerably more aggressive note. Again it is not loud to the point you cant enjoy a conversation in the JK but the exhaust note at the tailpipe is more noticeable for sure.

I have had both on our Jeep and I prefer the sound of the relocate with its more aggressive note.

Hope this helps.

MB