the metal hangers last longer, but the rubber ones provide a little more sway when you rev, shift, let off the clutch to fast, ect. (whatever makes your motor lurch). the best solution i have found (dont know quite how it effects performance) is the metal hangers and use one of those flex pipes (search "exhaust flex pipe" on summit.com and you'll come up with 50 of them) coming strait off the exhaust manifold before your pipes start. that takes the tension off your pipes from motor lurch, and provides long life to the metal hangers. just my opinion though.
