03 cobra

any of the combo's you listed will give you great gains. They will all be withing a few HP of each other. Just up to personal pref.

When choosing an exhaust combo, it's best to go with what sound you like the best. The main manufacturers of good quality exhaust systems will all make similar power. The difference is mainly in the sound. I'm not up to date on all the systems and how they sound, but I can however give you an idea about the Borla Stinger cat-back with a MAC off road x-pipe. It's loud as hell. But everywhere I go people are telling me how good the car sounds. In fact, just tonight, I took the wife and my 3 little girls down to Sonic for a milkshake. They were having a little cruise. I had several people, including high school and college students, middle aged men and even a man about 70 who drove a corvette all tell me how much they liked the sound of my car. Basically, it's all up to personal preference.

They are all so close in overall HP/TQ gains that there really is no clear cut winner. There was a magazine shootout way back when the first '03's came out comparing 4 or 5 different cat-backs. It might have been MM&FF I can't remember. All of them made approximately the same gains except one... The Flowmaster cat-back was down 4 or 5 HP/TQ compared to the others.

U.M.