I haven't bought a new bike in almost 10 years. All my bikes have steel or aluminum frames. I'm thinking about getting a new or used bike for my commute and am looking at some carbon-framed bikes. Does anyone use a carbon fiber framed bike to commute? The commute is around 35 miles round trip, roads and paved bike paths, every day. I've never owed a carbon fiber bike and am wondering about durability, locking it up on a bike rack every day, scratches and so forth. They should be fine, right?