I have seen more engine failures due to K&N (and other brands that use the same type filtration) air filters than any other engine failure in the line of work that I am in. It boggles my mind to watch folks throw away a paper element filter which the OEM uses, and put a K&N on it because "it flows more" and "it's cleanable". Sure. Just go ahead and save for that new engine while you're at it because you are GOING to need it. The failure isn't going to happen in the first 5 hours of use, so people tend to get used to the fact that it runs and runs fine. 100 hours later it's smoking and/or rattling, and they don't know why. The vast majority of the time (in the line of work I'm in), the equipment has and air filtration problem in those cases. I have done it myself on my own stuff. Live and learn. K&N's million mile warranty is also a joke. They won't stand behind their guarantee. None of them will, they ALWAYS find a way to get out of it. Went through it with a customer, K&N rep, and the customer's attorney. And K&N wasn't wrong, however the installation instructions did not specify to watch out for "that" issue during servicing.