Welcome to the boards.
DONT get equals if youre getting shorties. They are too much of a PITA and you will burn plug wires.
I would fork out the additional $$ for the Ceramic coated ones. They keep heat out of the engine better. Mine are 8 years old and still look new. I have FMS unequal ceramic coated shorties.
I have an xpipe, but I dont think it REALLY matters which one. grrrr says that the X sounds more like an exotic car, but I really dont know what that means, but he hasnt heard my car, b/c mine sounds like a Mustang.
Good Luck
RC