My 2 cents, about what its worth since we don't do hills...
We have v-brakes, and I wish I had a disc to drag on the rear, not that we're climbing hills large enough to overheat our rims, but I'm just paranoid about it. Every time we experience a new down hill I think how long is this, will this be a hill worthy of stopping to check the rims? As for the weight, if I was concerned about another pound on the frame, I'd go on a diet, which of course would reduce the chance of my rims heating...
