I did a search and found nothing. I was wondering if anybody had this. Is it better than a three inch cat-back. Also, It said header back but do you have to use their headers.

Here is a link to it.
http://store.allperformanceparts.com/?x=32&y=0

you wouldnt have to use there headers you would just have to use a reducer, but that kit is a universal fit kit so custom fabrication is going to be needed.

It would probably be better than a 3" catback with the stock ypipe, but the question is 'is it as good as a 3" catback with decent headers and ypipe?' Too bad it's not dual 2.5".