I've been more than pleased with the sound and performance of Epco exhaust the last two years as well. I don't know if they have changed the materials at all, mine discolored a bit at the header junction, but a little color on the headers and pipes doesn't bother me. Being naturally lazy and indolent I also neglected to apply sealant at the pipe/header connection, but the fit is so tight I can't detect any air leaking using soapy water (isn't that what the gas people do?). I initially waited a few months before removing the AI system. The headers on the 76 T-140 turned into a blue and gold rainbow.
