Is there a compelling reason to buy a metal-substrate catalytic converter as opposed to a ceramic substrate converter, assuming they are otherwise "equal?" I'm about to order a hi-flow race cat for my midpipe, and can purchase the Magnaflow I want in either substrate version, the metal being about $40 more. I don't mind the added cost, but only if there is some type of benefit.
The car is daily-driven, autocrossed extensively and will probably see 2-3 track events yearly.