I have Flo Pro originals, which is kind of like a welded turbo muffler with no packing. I like them. They might be too loud for people who want to listen to the radio in the car. The muffler shop refused to put on anything else after I blew up a Cyclone Sonic Turbo. That was a long time ago.
Naybor got one of those must4ngs with a muffler delete, so I was going to get Pypes Violators. He got a quieter system tho, so I left the Flo Pros.
I read the chambered mufflers like a Flowmaster for some reason get really hot. Don't know first hand if that is true or not.