i had a complete rebuild from piston, cam. crank, & valves because of bad air with 60 hours on the unit. i was using a uni, but no oil...stupid me. i also have since installed a snorkel to try and acheive a better source of air. i now have 2 stock filters, oiled, and the uni. i can swap and always have a clean filter. i can not stress enough use oil on your filters after cleaning!
K&N does make a filter. it is the same one as the rincon, but my dealer recommended against it. he was running a uni.