Yes, I agree with you both, oc_civic and white_n_slow. Quality is quality. Alumalite piping is standard tubing in most aftermarket exhaust shops. Will not rust. The problem with stainless is that it does not tranfer heat. During avation mechanics school, welded a 7 inch piece of stainless for 2 inches. Instructor had me grap the other end with my bair hand. Warm but not hot. The only benefit is that it does not hold heat. Cool running exhaust. As for a duel pipe, going from 2.25 to duel 2.25, reduced pressure with reduced turbulance.