Hi, I just recently bought a 2006 v6 Mustang and am looking into doing the same basic upgrades one would do for a motorcycle, ie, more open air intake, freer flowing exhaust and an EFI remap. I'm planning on a basic cold air intake, possibly with a ram air hood, the filter includes a custom EFI tune through Americanmuscle.com. I'm trying to decide what route to go exhaust-wise, and I'm curious what difference there is between a Flowmaster (or any basic muffler replacement) and swapping out the exhaust for a true dual. Cost is an issue but if the difference is substantial enough I'm willing to save and buy what's worth the effort. Sound is less important than horsepower and torque is best, but I'd expect gains across the board with this sort of large modification. Thanks.