Go with a K&N Washable engine filter with a million mile gurantee. Runs $58 with tax at any auto store and you will never have to buy one again. I noticed a 2mpg gain vs a OEM engine filter.
Building a Project X-tour, I could've bought a lot, I passed up a 2011 STI Wagon for the same price and Jaguar would've given me the difference on my old car to get it. I declined saying, "Don't get me wrong, it's everything I want of a car, I can make it into everything I want it to be far easier...They're just too common."
Working hard on unique and very difficult project, A Baja-Racing capable X-tour. So far, great progress but I go through hell to make smallest accomplishments possible.