I had a K&N on my 06 5.7 when I had it, and it worked great. When I traded it in for my 10 a buddy of mine put it on his 06 4.7. You could tell a big difference. I've heard some good things about the Varraram so I went out on a limb and got one. Took about 3 weeks for them to ship it from Varraram. Next monthe I'll be home and take some pics and post if I notice any difference in HP and MPG.