I want to build-up a new commuter bike, but I am not sure if I want MTB or Road components. The commute is 25 miles roundtrip daily, with occassional rain. What I would like to know is which type of components are going to be most durable and carefree for the daily grind and over the long run. Right now I am in a toss-up between Ultegra or XT (or DA vs. XTR if the wife allows for the extra$$$). Thanks for your insights.--gaijin