For 10 years now I've been using Hooker Aero Chambers. Best muffler I have ever heard. Quite but measurable at idle and low rpm cruise, and they wake right up when you get on it but its a smooth deep sound like no other. And at highway speeds you can actually have a conversation w/o much of any drone. They flat out rock and I just ordered another set of them.
I had flow-masters on my black nova and there was a heavy drone at any highway speed. Hooker's are way better all the way around. I'm loading a video for you and will post it in a few minutes here.
