I have a Weapon R intake, and it works great, I noticed a pretty big performance increase after installing it. I did do some shopping around before I bought it and if the numbers are right it actually dyno'd higher than most intakes that were available for my car, that includes KnN and Injen. I'm sure it'll depend on the car though as far as what's best for it. Weapon R is also a lil cheaper compared to some. They range from about $150 to $300.