ive got 1 of those new jammin pipes on my new s7 2 engine and it has great bottom end
its the only pipe ive run on that engine so i dont know how well others compare but i do know i have enough bottom end to keep me happy even with a out the box clutch set-up on a motor that people tell me lacks some on the bottom end
my old motor was a P5 so i do know what good bottom end feels like
the clutch is a aluminum shoe set-up with 1.0 springs
so based on what i do know i would say the jammin pipe has given me good bottom end power and its extremely durable and the best part i picked it up off ebay for about $60 shipped