Magnaflow cat back DIY installation?

[C5A4]

Well I went and paid $70 to have the exhaust installed, that way I have my old one still in case I want to go back. I had the exhaust on first and really didn't notice any performance gains other than the nice sound. The sound is loud when taking off but at cruise speed its a nice low rumble. I think its a little louder than I was wanting. It does look nice comming out the back with the dual tips. I then installed the AFE intake and that seemed to give the performance gain. Or the two working together I'm sure. The thing I need now is the programer. I think I will be getting the Predator.