Bill:
some of Us use them a couple of months a year just before the rains, some years the dirt has turned almost into powder!. But I admited, I am lazy since this filters need to be wash before the next sunday so the engine breath right and I don`t always do it, so I don`t always use them.
I stick to after run oil.
Thanks Bill for remaind me, I will put the filters back this Saturday, it is time.