I'm trying to learn & understand more what my options are for achieving the best bike for commuting cross country to work in the spring & summer as many days as possible. The distance is about 15 miles & is all pavement but bot pristine pavement. I recently became aware of this bike class & I'm thinking my commuter should have cyclocross attributes but I'm not sure which bike to work on. Both are old beaters so I can pretty much do whatever ever I want. So what's your opinion & why? Roady or MTB?