Ok that was a stupid question i never really trusted ebay. i did find out that the top of the line chips come down to the SCT XCalibrator, and the predeator. i am interested in the mustangtuning.com one (the x cailibrator) they are selling it for $299.99.
Gains on stock GT's around 17 RWHP and 20 ft-lbs of torque. More on V6 and S/C Cobra.
Remember, these are stock numbers. Gains will be higher on modified vehicles.
Though there appear to have no garentees or warrentys. i am considering it what do guys think...