I have the Injen CAI, but I installed as SRI for now because I didn't have time to remove the bumper and what not. I'll finish on a later date. for the most part the Injen has shown a good increase on my gas mileage. I've gained just under 60miles to the full tank in comparesons to a full tank with like conditions with OEM Air Box. Sounds pretty mean and looks good to me. I can get you one for a very good price if you PM me. Authentic Injen CAI from Injen direct in Pomona. If you live in the SoCal IE or OC area, let me know. I have no idea about the AEM, but both companies are very reputable.