In theory the Mach 1 should have a better resale value due to the fact that it is a limited edition and available only in 03/04, while the 3v is mass produced since 2005 :idk:
Trust me, it's simple.
The bassani X pipe has a kit to allow you to remove the cats and have an o/r if you like
All it is, they provide you with 2 extra pipes incase you want to delete the cats and put the pipes instead