MUFFLERS, what should i get?

Dyno Max Ultra flows .
These have a dual,triple personality, which is why I love them..
When you are being nice, they are reasonably quiet(on my 367combo at least).But when you stand on it they have a wonderful, get-outta-the-way-I'ma-comin-thru, scream. The rest of the time you can vary the sound with the gas pedal. And mine do not have any tendency to drone.I have received Zero negative comments on them. Well just one;from me. The pair weigh around 70 pounds.