I'm guessing the catback is used because the up/dp combo is cheaper than the catback by itself. I would say get the catback first for the sound and then when you have the $$$ get the dp/up combo to save the $50 but from what i've heard the evo catback isn't that much louder than stock, so without the catless up & dp you might not be that impressed. Since this is probably a used catback like mentioned above, if you are saving half the price of the catback - you might wanna jump on that deal right away which solves your dilemma. If you aren't getting a used catback, and you are assuming you would have to pay somebody to put the dp on...don't. It's really simple to do by yourself. The up-pipe on the other hand, was a pain the ass, but again, nothing you and a friend with some patience and automotive knowledge couldn't handle.