difference in fuel system, exhaust and tune but i didn't know you couldn't get a predator for 96-7......interesting. I'm not a Diablo fan myself, i prefer SCT because they offer a huge support network and have more mainstream tuners available.
is the chip installed and tuned already? If so i don't see a reason to switch...when someone is shopping around for tuners/chips i think SCT is a better choice but if you already have the Diablo chip installed then getting any other chip or tuner is a waste of money. You can just go to any Diablo tuner in your area and have adjustments made....just what i would do. You will save yourself money. Your local tuner can make every adj to that chip that can be made with a handheld.