I've been looking at performance upgrade options and want to keep it simple. What is the general concensus here on the Cobb ECT (Stage I)? Is it worth the money, and can you really feel the difference when it's installed? I'm also worried that if I install this thing it might lead to detonation, as well as possible voiding of the warranty.

What about getting a piggyback unit instead? Seems like warranty issues would be less likely since it could be removed.