And commuting even a couple miles on Philadelphia roads is basically like off roading at times - and San Francisco hills are legendary in their own right. I was rattling my brain out of my skull trying to deal with rough Philly roads in the winter and a proper carbon bike with good brakes/ability to stop on a dime if a crazy driver is cutting me off (I have heard legends of these things called "protected bike Lanes" - I hope to see one someday...) was a godsend.