2008 M6 vert 6MT: Borla cat-back exhaust installed just before I bought it. Looks very nice (3.5" dia quad tips), and in as-new condition, but is too loud for me. It doesn't drone especially at interstate speeds, but I would prefer to advertise less. Anyone interested in a swap for a quieter aftermarket exhaust? I could be talked into an OEM exhaust as well. I live in the upstate of South Carolina.