High flow cat question
 

My exhaust has rusted off completely, I'm in progress of buying Header/cat/catback and I have a question about the high flow cats. All those ebay ones seem to be test-pipes even if they state that it is a cat. We have emissions every year and I don't want a hastle. Does anyone have any experience with that and does anyone know if there are CARB certified ones out there.

I'm looking to buy a Holley 4-2-1 header and a Holley M/A exhaust. I heard that they're pretty load, but are there any other opinions on it?