I've used a product called RIG for over 25 years, and I find it to be the best protectant for the exterior of my firearms. I stress exterior as I do not think it is recommended to use as a lubricant, or a bore preservative. It has a waxy color and consistency like Cosmolene.
I've been using the Renaissance wax from Midway for a couple of years and don't envision going back to light oil. Back in the 80s, I picked up a product at a gun show that was the best ever. It was a red cotton cloth saturated in something. Touch the cloth to your fingers and wipe down the gun. No residue and no fingerprints. Would love to get my hands on some of that stuff.