The K&N recharge kit comes with a bottle of cleaning fluid and a spray can of oil. The process is very simple. Just take off your air filter, spray cleaning fluid liberally on the outside of the element, let it set a couple minutes, spray cleaner again, wait a couple minutes then with mild water pressure spray from inside out until water coming through is clear. If at this point the element is still dirty then repeat process, if not let it dry completely before applying oil. The only trick to the oil is do not over apply, just a light coat is all that is needed to the outside only.
I have had very good experience with K&N, I even ran one almost 500k before I sold the truck and it still worked fine. I have them on the RSV and my new truck also.