Frog Lube works for me. After a few years, it starts to turn dark, but it cleans off easily with some degreaser -- ready for another coating.
i like that it is a dry lube. It doesn't collect lint, hair and dust as much. When you take it to practice, the heat causes the lube to liquify, providing more than enough lube to operate.
I used a heat gun to melt/bake the lube into the metal. I like that i won't be grabbing an oily, slippery firearm from storage if I need to use it immediately.
Tests on YT convinced me, in that Frog lube resisted rust longer than every other lube/protectant they tried. Things might have changed since then, but it's been good enough.