Personally, I would set the carbon bike aside for now. How many pinch flats do you really want to repair? Pick up a nice steel MTB or hybrid from the 90's for $100-200 and go at it. I just converted a lugged steel trek 930 MTB to drop bar, and am getting ready to do the same to a lugged steel Trek 790, which has the same frame as the 520 touring bike. No reason you couldn't do a two day,150 miler on either one.