Interesting question but really hard to answer. (For me at least). The sound of the engine is a very subjective thing. There is a guy here at work with a newer Mustang. He has a Borla cat back system. He loves it, but I just find it annoying. His car, his money, what he likes is more important.
What I have on the truck is 2 1/2" back to Magnaflows with the pipes exiting to the side behind the rear wheels. The Vette has 3" all the way back with Magnaflow's. I love them both though they are on the loud side. My neighbor says he doesn't need his alarm clock when I come in to work driving either vehicle. Fortunately he likes hot rods almost as much as I do. It is fun going into a parking garage and setting off the car alarms...
