Love my CAI. I installed an AFE kit, then sold it and went back to stock. Going back to stock was so painful that one week later I ordered an Airaid kit.
It was like the Jeep was breathing through a straw again. Just fell on it's face. Throttle became jerky again. Needed more pedal to achieve the same acceleration. The Airaid kit fixed all that again...this time with the added protection of a fully enclosed air filter box.
The engine response is night and day. Power is much smoother and the Jeep gets up to speed with less throttle. It's noticeable with no dyno necessary. Fuel economy is unchanged. So don't buy it just for gas mileage. But the sound and added power and throttle feeling is worth every penny, plus you never have to buy an air filter again. Ever.
If you think about it, it's a much smarter mod than adding huge tires and lifts...because instead of losing money, you're actually gaining money over time as well as driveability.