I just have a 2000 5.3 but the Gibbsons I have is awesome! Quite at low RPM and nice and throaty at high. It coast more but I get 2-3 more MPG and its been on my truck since 2001 with no cracks or brakes in it. And you don't hear it at all on the high way.
I would say Gibson or Borla. . . There is a reason they coast more. But Don't get me wrong. . . back when I was younger I loved the sound of Flow master. And if its installed rite its an awesome way to go. If you don't mind the deep loud throatynes of it.
Either way it just depends on what you want. . . Deep loud, Throaty with Flowmaster or Quitit tell you want it with Gibsons or Borla. You just have to hear um all.
And as long as you have it installed rite. It should last.
