I'd be careful with the MBRP race series. While it sounds great at idle and driving around town, the drone on the highway is insane. I know because I had that catback with lethal's off-road x pipe and the drone on the highway was just too much. From there I ended up getting bbk headers and went the gt500 mufflers and JPC over axle pipes to delete the resonators and get rid of the poorly designed stock squished over axle pipes. This was a decent setup, but I wanted something a little deeper sounding so I switched the axle back to the magnaflow street series. Personally if you like the sound of the gt500s I would say have an exhaust shop do the resonator delete, or get the JPC/lethal over axle pipes, and eventually get some headers. Here is a link to my current exhaust setup https://m.youtube.com/watch?v=KHfenkhWfus
2014 Mustang GT 6R80, Procharger Stage 2 D1SC, BBK 85mm TB, Boss IM, Sai Li fuel system. Circle D 3C, 1-7/8" Kooks Long Tubes w/Offroad X Pipe, Lethal Over-Axle Pipes, Corsa Quad Axle-Back, Eibach Pro System Plus, BMR K member, Shaftmasters DS, Forgestar CF-5 Wheels and Nitto NT05 tires. Lund Tuned
Lots of suspension goodies and some other stuff I can't remember.