There's a lot of misunderstanding about "conductive" and "non-conductive" lubricants. Very, very few "conductive" lubricants are conductive enough to be any help in conducting heavy flashlight currents. Typically, they're many orders of magnitude less conductive than metal, and the reason they're conductive at all is to dissipate static electricity buildup. There are a few specialty lubricants which are highly conductive, but they're uncommon and quite expensive.
You want a lubricant -- non-conductive is fine -- on all your moving contacts. The reason is that aluminum and tin, in particular, oxidize immediately on contact with air. The oxide is very hard, brittle, and non-conductive. Each time contact is made, the surface oxide is shattered and pushed down into the softer metal. After a while, you have nothing but shards of oxide for a contact surface. I've seen a photomicrograph of this, and believe me, it ain't a pretty sight. The function of a lubricant is to keep the air away from the metal so it won't oxidize so readily. The pressure of the contact forces the lubricant out from between the contacting materials. So you end up with a better contact.
Electrically conductive lubricant is generally not a good idea, if there's any chance any of it can migrate into regulating circuitry. There might be places in the regulator circuit which are high enough impedance that even the slightly conductive material could cause a problem. I'd avoid highly conductive lubricant altogether because it could really screw things up if it got where it didn't belong.
If you need to see for yourself, try it out on one of your lights that has an obvious contact area you can easily get to. Keeping some lubricant on your contacts will give you more consistent, reliable operation for an extended period.
c_c
Sometimes when I use it a get weak, dimming, or no light. Samething happens with the twist action. Is something wrong with my Xo3? Or is this a user related problem? 
