It's nice to kill two birds with one stone: turn your commute into your workout. My Garmin says it burns about 1200 calories (27 miles round trip). It doesn't suffice for road racing training but it's still a great work out. I don't like to commute with my road bike since it's more prone to theft as I have to leave outside my office. It also doesn't take pot holes too well. I use a Specialized Sirrus, which yes, is also a very nice bike and prone to theft, but it has a back rack for my tremendously heavy U-Lock and better handle's Chicago's punishing potholes. I take a street in Chicago known as Elston Ave., and like many other posters on here, my commute takes about as long to drive as it does to bike. I often snicker at the cars who are in a traffic jam on the wretched Kennedy Expressway. If I am feeling tired or sore from weight lifting the night before, I can bike to an EL station and lock it there. Saves money for gas and parking. Just an easy 3.5 mile ride one way.