From your list, my choices would be Thomas and Benson, but that is a tough list to choose from.
The risk with Thomas is the QB situation in JAX.
Cleveland was bad against the run last year, but the funny thing is that they did not allow very many rushing TDs.
I think that Shipley could have a good year especially in a PPR, but I think that Benson is a safer choice for the first game of the season. Shipley would be my 3rd choice.
10 team, PPR, 1 qb 1rb, 2wr, 2flex (rb/wr/te), 1k, 1dst
QB: Stafford, E. Manning
RB: Peterson, Blount, Hightower, Starks, Tate, Tolbert
WR: Nicks, Wayne, Bowe, S. Johnson, M. Thomas