I think I would avoid both right now. I don't think that Murray is the clear cut #1 if Jones is healthy. I don't like to remove games from someone's stats, but outside of the St. Louis game, when St. Louis was beyond horrible at stopping the run, he averaged about the same as Jones per carry. I drafted Jones and was quite upset when he got hurt right before he got to the nice part of his schedule and I didn't have a high enough waiver spot (unfortunately on the team with the shortest bench of all my FF teams).
After Murray got hurt, Jones played quite well. I wouldn't be surprised to see a real RBBC approach as I think both are about as good as each other and both have already had injuries missing games. Maybe more like when they had Barber and Julius Jones, although I am not sure who would be the goal line RB.
Unless one really shines during pre-season and is named the unquestioned starter, this could be a bad situation where you have to draft two players and neither, without injury, produces. I have seen some top 100 lists and I sure wouldn't draft Murray where he is projected in the 2nd round.