Injen is alot more reliable than K&N. In terms of horsepower gains you really won't see a big difference between the Injen or K&N but I would trust Injen more. Theres plenty of other modifcations you can do to your car to increase torque and horsepower. You should invest in an ECU chip tat will change the engine mapping of your ca. You'll get a significant increase in hp but youll need to go with 93+ octane. Turbocharger, turboback exhaust, uppipe, downpipe, engine specific camshafts are just some of the many modifications you can performe on your car to increase its horsepower. Decresing the weight of the car will also help alot as well.Ok first off "Phantom" or whatever you prefer to be called. K&N is known for making under-par products with their air filters. I know this because I have friends who have used K&N air filters and they've been nothing less than garbage. Now you tell me why I would go and recommend a company product that doesn't work very well? Tell me this buddy. You don,t seem to be providing this man with any gelpful answers or tips besides your useless and obvious facts you pull from a website. Next time you try to call someones comments stupid, so some research a bit, maybe then yo won't look like such the flaming retard that you are.