Catalytic converter options
Posting it also here in the hope that someone has experience with KSP or SARD cats:
Being 8 years old the cats failed the SMOG test due to high CO at 2500 rpm. They're 300 cells (Prospeed style but a different brand) with a perfect fit for 600 bucks back then. Car has a CTSC system.
What are the options nowadays? They should keep up with the CTSC but also guarranty SMOG for some years (the more expensive - the more years of course).
I've seen the ones from SoS, SARD and KSP.