That 2.5" magn catted xpipe has been on my car for ten years and works excellent. The cats are durable. I have had zero issues with it and this car has been at 22psi and over 700 wheel for over a decade. And that's with factory manifolds. No issues at all at inspection time....but we don't have a sniff test here so I can't guarantee it will pass in komifornia......but I bet it will, especially on E85. They ought to pay me $$$ for how clean I keep the air