I'd probably take the trade. You have depth at RB and CJ would totally help at WR (obviously). I know it's hard to give up McCoy but CJ is the real deal. This trade makes your team a more all around good, complete team. Good luck!
QB- M. Ryan, T. Pryor
RB- A. Morris, L. Bell, A. Ellington, C. Ivory, M. James, D. Martin
WR- J. Nelson, A. Brown, J. Boykin, D. Heyward-Bey,
TE- J. Graham, C. Fleener