[jeff88]

I went to my local smog station the other day and he started jacking up my car and looking underneath which I've never seen before for this procedure. After he was done he said that my cat is not compliant with the state. For some reason California decided to change which cats they are OK with and which ones they are not and they didn't grandfather in the invalid ones. I've had this one for multiple smog tests, but now all of a sudden it's a problem.

So... I've been reading up on cats and everywhere I read it seems that it really doesn't effect FE which cat you decide to go with, none of them will make a noticeable difference in FE.

After researching, my only question is this: does it matter if I go with a direct fit for $300 versus a universal for $150? Labor cost doesn't matter, my friend/mechanic will be doing it. I don't have an aftermarket exhaust system, everything is stock. Does one work better, provide better FE, or last longer?

Thanks!