I have the JET chip currently before I order one from Brian. I was getting this horrible idle and it would stall out on occasion. Over the last two weeks I spent a week with it in and the last week with it out of my X, I must say without the chip I actually have better performance, I could notice the shift point difference with the JET chip however.. Now that I have been running for an entire week without the jet chip in my idle has returned to the smooth runner I have come to expect. Jet may make chips or programmers for other applications that prove to be useful but I wouldn't buy one for my X again. Also you can't really beat the price Brian can reburn or retune your computer and he doesn't charge anymore than any other chip/programmer manufacturer. I would and am going with Apten.