I installed this muffler on a '95 F-250 with a 460 big block in combination with a QTP electric switch. The goal was to get a normal sounding but slack exhaust with the option of a straight tailpipe. The damper does its job very well. The truck is just as quiet as it was with the stock throttle muffler and the (very) restrictive 24" catalytic converter, but the straight-through design offers very good flow characteristics that didn't affect my performance at all. Highly recommended for anyone who needs a quiet but smooth muffler. I've had the muffler on my truck for almost 9 months now. The stainless steel discolors easily with heat and also holds on to road grime, but it looks like good quality stainless steel that won't rust itself.