No offense, it would be nice if there was more concrete evidence for the mileage rather than "they must last longer than oiled chains, look at how dirty they get!" The guy on EcoVelo is estimating as well, and lives in about the perfect environment to use waxed chains.

The solvent-and-oil process needn't be as messy as most people make it, either -- the thing is to wipe the chain thoroughly after oiling, then wipe it periodically to remove the oil that works its way out. I'll succumb and try waxing a chain someday, but I'll probably use a greater proportion of beeswax and throw in a little grease for better lubrication when I do.