Uh, not sure who told you you don't gain much. You will definitely gain power from 5500 rpm on and more importantly, you can extend your redline out to at least 7500 rpm. You don't really lose anything in the lower revs, you just don't gain anything either. Definitely worth the $500. I love mine, the way it sounds, and once it was tuned the car drove like a completely diffrent animal. I'm very hard on my car too.