I had this company make my stainless pipes. The 4" muffler body is, the muffler. No muffler breaking of the welds causing rattling. No glass packing to burn out.
No more cost of ceramic coating and constant polishing. The collector is a venturi with welded "stars" to aid with flow and fluttering. They are very highly polished. The cost is high but, they should last for many years vs. mild steel and re-coating them after a handful of years.
When I receive them, I plan of dyno testing these vs my old side pipes that are from Lone Stars kit. I can't wait to see and test them and find out how much HP/TQ I'll gain.
http://fireflyperformance.com/