Hoppes #9 is a gun solvent - not a lube. RemOil is also a cleaner - but with a lube. Aerosol cans of it, available at Wally World, permit blasting innards with that little tube to dislodge grit and grime, yet leaves a fine oil after the solvent runs/evaporates away. Both it and BreakFree, also available at Wally World as an aerosol, contain minor amounts of Teflon as a solid in suspension. Shooter's Choice's FP-10 supposedly has a metal treatment, MT-10, as a component, but no solid lubricants.
I use mineral oil, a drop spread over - carefully - the entire length/side of a carbon steel blade for protection. SS knives get washed after use - and their blades are left dry. If I lived or stayed near the coast - salt spray - I'd use mineral oil on SS, too. It is an 'edible' oil, great for kitchen knives, and especially if you have constipation problems...
Three-n-one isn't the 'best' oil for anything. The lighter components evaporate away in time, leaving a thicker oil residue. In the home, immersed in dust, mainly from human skin cells, pet 'dander', wood dust, dried vegetation ash (cigarettes, etc!), etc, it 'accumulates' some - making goo. That gets thicker as the lighter oil components evaporate - like the resins thicken linseed oil. Add a small amount of metal, like the blade/mechanism as a catalyst like Japan Drier in a varnish, and it's easy to see why the result, in time, is like varnish... it likely is varnish! And - oil is normally a dielectric - and won't 'attract' dust - it just won't let it go once it lands on it.
Imagine how much 'dust' is in your lungs... But, to lessen the dust problem on your knives, keep your knives lubed in a tight display case.
Stainz