Lets compare apples to apples and oranges to oranges here. "Race cars", for the most part, use alcohol, not gasoline as a fuel. Burning alcohol creates little or none of the noxious fumes gasoline does. This is the reason racers dont use them and why the rest of us do. We burn gas, we use cats. So this whole thread argument has been MOOT.

So given the original question, as to which catalyst is best...I have never used an aftermarket cat, yet. But I have bought OBX components, notably a muffler and short shifter. The muffler was alegedy Stainless steel...it rusted. The Shifter was...cheap as hell, and felt it. OBX, as far as I can tell, buys crappy products from asian sweatshops, then packages them in a shiny package, and sells them for ten times what they are worth. I will never buy another OBX component.