It's programmer, bored throttle and CAI in one. I like the idea it was just out of my price range. The idea sounds good though, most people like bigger TB's and CAI's. Not sure about the tuner though.
Never been in a xj with it, but I have put them on a few tj's. I was pretty impressed, but they are pricey. Do the air box mod, get a jet chip for close to same results for a lot less $$