Quiet doesn't mean restrictive, nor does loud mean best flowing.
Car Craft, and others, have done a number of tests and the Dynomay Hemi muffler is the winner. Quiet, free flowing, cheap. On the dyno, with a sound meter, real tests not someone's guess.
I agree with you but most stock mufflers I have seen are both quiet and restrictive compared to an aftermarket turbo style muffler(dynomax). The 5/16 fuel line is sufficient.
