hoenstly, i think this muffler is built really well. it literally has 2 cones facing each other with in the muffler. so imagine 2 traffic cones of point to point. they are made out of a heavy gauge screen material, but the wholes are plenty large enough in them to not worry about soot build up. sound goes in and hits the cone screen material, bounces towards the outside hitting the packing and then fills the packing chamber and then exits the other cone. mean while....its still a flow straight through design. i can not feel any performance loss. also, even looking more into these vs other mufflers/resonators. majority of the other mufflers/resonators are 5-7 inched in diameter. this one is 9 inches in diameter. obviously there is more packing in the unit as well which i think helps.
i now have 5000 miles on this muffler. I actually like it better when its broken in as it was to quiet when i first installed it for my likings. its had a nice rumble at idle but nothing crazy. whistle is cut in half on my danville 3794 with high flow vanes! love it!