I've been commuting on mountain bikes for 2 years. Just decided to get a road bike this weekend - wanted something lighter and faster. At points on my commute I have to carry the bike up several sets of stairs, etc.... even though my MB is pretty light, it can be a load.

I'll probably throw some GatorSkins on there to be safe - I do a fair amount of night riding and it's impossible to avoid every piece of bad road.