I have a 1999 Ford F250 Superduty (early 99, 12/98). I'm considering getting a performance filter, but what's wrong with K&Ns? What is it about the K&N that causes so many problems? Why are others so superior? By the way, I noticed some manufacturers offer a OE style filter and an intake kit, considering I don't really push the truck, and usually run at about 1,300 to 1,500 RPM. Is the intake worth the extra $200 to 300?