TTI will give you the best fit for the exhaust system from front to back, but the muffler choice is purely up to you. You will see every single manufacturer praised/slammed for the sound, depending on who you ask. You need to hear them yourself to decide. Personally I have the Flowmaster Super 40s and would not change them for the world, but Billy Bod down the street will say the same thing about Dynomax, etc etc..