[200q20v] Discount Convertor?

[TM]

Anyone here use discountconverter.com, especially on a 20v
turbo car?

I'm trying to get an idea of how much a cat will cost for my
car- I need the passenger side cat. I'm also concerned about
whether or not the replacement cat has equal or better flow
characteristics as I don't want to put on an overly restrictive
cat. I'm not putting on test pipes as I may not be able to
pass inspection that way.

Taka