i just had my custom exhaust fabbed up Friday. it is a Magnaflow X-pipe going into two Spintech Pro Street muffs and out Borla Intercooled tips thru 2 1/2" tubing. That's mated up to my SLP LTs and 3" race pipes. The sound of the Spintechs is AWESOME... unfortunately it is also too LOUD! It sounds like someone adjusted the bass knob all the way and turned the volume to MAX. You can't make it quiet idling, cruising or accelerating but the WOT is incredible. i got the Pro Streets because they are only 12" long and i thought i'd have a problem getting bigger ones in there. after arguing with the muff shop owner that they would fit we could see that the 13" Spintech Sportsman muffs (which are quieter) would have fit too. i also had to argue about using 2 1/2" tubing and not crimping it like the stock pipes. what we did was run the passenger side pipe straight back past the diff and then wrapping it around it to exit out the stock '04 exit point. it worked beautifully and makes me wonder why they had to crossover and crimp the stock pipes. On the sound i'm going to have to find a way to lower the volume. i've got 2 Dynomax race bullets coming to put on the 3" race pipes where the cats were to see if i can lower the volume without altering the tone or affecting the high flow rate. i'll post up how it went next week when i get back from Vegas