There is always lots of discussion about air filters, and I believe you can make a case for not using a filter at all.  It depends on how much ground running you expect to do and the atmospheric conditions.  One takeoff at a dry, dusty, windy airport might cause as much wear as 1,000 hours of ingesting clean air.  So, if you are willing to be cautious about the conditions you fly in, I suppose that works.

But most aren't willing to take the risk - I wasn't, anyway.  But then I see lots of comments (also among car enthusiasts) about K and N filters.  They are truly better - about advertising.  Too bad their filters aren't as good.  I've tried to get information from them about filtration efficiency and I've only got vague references to it being "really good."  Somewhere I have a technical paper that compares their filter to typical paper filters.  Theirs has a filtration efficiency, when done according to SAE standards, of about 92 and maybe 94 percent.  That sounds pretty good in the ads - only 6 percent of the dirt gets through - by weight.  But most of the particles are small, so if you want to count particles, a lot of them get through.  By contrast, a typical paper filter has an efficiency of about 99 percent or more.  The newer technology can be 99.7 percent  efficient.  So that says the K and N filter passes at least 6 times and perhaps as much as 10 times as much dust as a paper filter.  And the paper filter isn't just "paper," it is a very high-tech blend of natural and synthetic material.  True, the paper filter of the same volume will have more restriction - probably twice as much.  The power reduction might be something like 2 percent with a paper filter and 1 percent with a K and N, but more like half that if you oversize the filter a little.