I can't say enough about hemifever's programmer(SCT DCX 9550) that I recently purchased. I have experienced a lot of improvements over the years with upgrading performance parts on camaros, and firebirds(headers, gears, manifolds, intakes, ignition, etc.) but the way this programmer changed my truck is hysterical. It went from being a dog off the line and barely going up hills to a completely different animal. My truck launches nice and hard from a brake stand, and hauls up hills. Donuts are even easier to do as well as burnouts. This is my first experience with a programmer, and I really didn't expect a tuner to do this much. It was worth every penny of the $265.
Warning!!! The addition of this item to your truck may half the life of your tires!