I want to call my reader's attention to a post on 24HourCampfire. One of the readers posted an article where he evaluated 46 products for odor, compatibility with polymers, lubricity, and corrosion resistance.
The two clear winners were Hornady One-Shot Cleaner/Lube (dry) and Frog Lube (wet). Shooters Choice Rust Prevent receives an honorable mention.
It should be pointed out that these products are also superb for bicycles and other gizmos that get used hard and sometimes see sweat and rain.
Do yourself a favor and read the series of posts by DIYguy.