SADLDUP

Has anyone here ever used a Jet Performance chip, and if so can you tell me the pros and cons on it. Also would a 2003 GT chip be compatible with a 2000 GT?

Chopper

A generic mail order chip is just that,generic.To get the most out of a tune you must go to a dyno shop and have it tuned while on the dyno.That being said,if you have an automatic trans you will get better shifts with a chip than before and performance will increase somewhat but you might have to start using premium fuel because of the new timing curve.
The chip makers will have to answer the one about the years but I will say no.There is a code on the ECM that the chip burners will need to know before they can make you a new chip.