keep in mind that the "X" and "O" ring chains have lube inside of the roller and the ring is there to seal out the water and dirt. The outside is still exposed to the elements of course, so you need to be sure and clean and inspect it just as you would any part of your bike. Dry film lubes, such as the one I described above provide protection, without the negative aspects of the waxes and oils.....no mess, nothing for the dust to stick to. Again, it goes on as a liquid and dries to the touch, provides protection, displaces moisture, and does NOT attract dust or dirt. Won't harm your rubber rings and lasts. I ride desert races, the dunes, MX with my 450 and the chain looks like new still, the chain on my sons Blaster is 4 years old....no kidding. It's good stuff.
There are also graphite based sprays out there as well, but the names escape me at the moment. Remember your not really LUBING a "ringed" chain, your cleaning and protecting it from the elements. The lube is internal. I'm just say'n