You have to ask yourself what you plan to do with your car. If you just want it to sound good, check out mustangexhaust.com or go to a few local car shows, talk to some 'Stang guys snd see how their cars sound. You also have to think about looks...side-exiting, pipes or dumps? And in the future, if you decide to run a panhard rod and/or a torque arm - those tailpipes are going to either have to be removed or modified. Even with exhaust you have to think ahead and not get something that will mess with something else later (ie side exiting exhaust blowing down cones) Personally, I went with a Mac Prochamber (no cats - I'm allergic) and Mac Pro-dumps. I don't sound like any other Mustang I've ever heard (which I like). At idle its a nice rumble - but at WOT every person at my SCCA events know who's running - the ROAR is unexplainable. People with all sorts of different sports cars get in my car during a run and say "I wish my car sounded this cool". I get all sorts of compliments on my exhaust...and the question "where are yr tail-pipes?". The MAC stuff is made well, performs great and is price very reasonably.