Yeah, cleaning K&N filters can make them last longer, but even when new they aren't worth using. The only filters you should clean are the oiled foam ones commonly found in dirtbikes.
Those of you with street bikes, check out rock auto for filters. Cross reference the manufacturer's part number. I found some there for a fraction of the cost, even less than amazon. You could probably buy 3-4 for the price of one K&N. Change it out every 10-15k miles of normal use, and it's gonna last you a long time.