I just installed a POWR-FLO air filter I got from Martel Bros. Made by JET performance products. Nice looking filter. Fit nice and snug in the stock air box. It is the oiled foam type, very similar to Amsoil Two stage. The thing I like is that the end of the filter is open, there is no cap like the cone on the stock filter or the flat piece like on a K&N. Air should flow straight into the intake instead of around the end. Have not driven the truck yet, but am curious to feel any differnce. Not hoping for much, but will take anything. Anyone else using one of these? Price is not bad either, a bout $15 less than a K&N, 2X a stock paper.