been driving open downpipe for about 2-3 months now. its nice when you get a really good backfire and you feel it in your ass, lol. its not that bad, except when i drive somewhere like orlando/miami, the interstate resonating sound gets a little annoying, around town it doesnt bother me, and ive had no problems with the coppers (knock on wood), they see that stock muffler hanging in the back and dont know what to say