The previous owner of my toy had the 40 series Flowmaster single in dual out with 3" chrome cannons installed out the back. I bought it with 41K and by 50K the guts were falling out rattling and the resination was so loud I could not hear my wife nor the 5 year old twins in the back seat at any speed. Wait, I think that was the goog thing.

The chrome was so rusted I could not make any part of them shine.
Point being watch what you get. I got lucky and found a single in/out Bosal stainless 3" that has great bottom sound, sets a few alarms off, and at 80 mph there is no resinense at all. My coworker that has hearing aids can have a conversation from the back seat with no voice raising.
Good luck.