I bought a Jet Stage II chip, I run a K&N air filter, powraid TBS and dual(not true) exhaust, i never notice a difference when i put the chip on, but when you take it off you relize you lost some power, it slowly gives you more hp over the course of 50-75 miles but when you unplug it, your power loss is intantaneous. Ive heard the shifting on the Mopar perf computer is very hard, that is the only thing that worries me about it. I like the way the jet 2 chip shifts, firm not hard, better than stock i think.