Hmm, I've only ever suffered one chain breakage, and that was off road with a knackered bike anyway.
I've got personal experience of at least half a dozen snapped belts on H'D's (one went rolling backwards out of the workshop!!) and the biggest belt breakers of all, Buells.
Chains have a massive safety factor, given good operating conditions. In fact, if one does snap, you're more likely to lock the wheel as opposed to a belt, so maybe the belt option is the one to go for!
