I have unfinished tongue & groove pine paneling on a ceiling of 1 room; and on the walls of another. It is only a few years old but appears no finish was applied. I'm not interested in staining - I'd like to keep the natural color - but it needs protection. Any comments on the pros/cons of using tung oil (or some other oil/wax) versus poly? Any suggestions for the actual product? And anything I should consider about the actual technique of applying one or the other?