You see this endless debate in firearm groups as well. As long as you are maintaining the metal surface, either oil or wax both work well. Museums tend to use waxes. They take more effort to apply, but give a longer term protection. They are also being used on items that don't get very much handling. Oil is less durable since it can be wiped off easily... but its also real easy and quick to reapply. It kinda depends. There's no one best way, and there is no one best product. If I have something that's getting handled regularly, I just wipe it with oil. If I have something that is being put away and I have no intention of using it again any time soon, I might break out the wax if I'm feeling ambitious.