I've got 800 miles on mine and can't wait to chip it. For the cost and what I have read on the forum, you can't beat the JB. I have been chipping diesels since my 95 Ford Powerstroke and never had an issue doing it. I enjoy the passing power, as long as you don't beat on it, your fine. It's the most expensive car I have owned and don't plan on beating on it.