IMHO I believe that the Fram Airhog is better than the K&N filter. I have personally used both for about a year each and I have to say that initially both filters start out great and sound awesome. After 8-9 months the K&N losses its growl and doesn't have as much punch as it did initially. The Airhog after 8-9 months still sounded good and felt pretty new. They are probably a lot factors that could have given me these results but this was all done when my MTX SHO was stock, oil was changed as scheduled, premium gas was always used(Sunoco) and driving styles remained the same for both filters. After a year of use for both I would just sell them on eBay. I'd just buy a new filter rather than bother with the cleaning and oiling. I also forgot to add that I achieved slightly better MPG with the Fram Airhog. Using either filter indefinitely boggles my mind but I guess that it is all up to your personal preference.
As far as these filters vs a paper filter goes I have nothing to add because that would be a different topic and the debate can go on forever. Personally I really would care what brand, style or color filter anyone uses just as long as you change your air filter regularly because no SHO motors deserves a dirty filter

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