Wow, tons of great stuff here all. Thanks for the responses.

To answer a question above, for me the fitness aspect is an added benefit. I want to commute because I love to ride my bike. I plan to ride hard and by keeping around an average of 15 should be a pretty good pace I would think, especially considering the major uphill portions of my rides home.

Along with some light weight lifting at night and tiring weekend mountain bike rides, I think I'm setting myself up pretty well here.

Thanks for the thoughts all, definitely appreciated.