Looking for Feedback about who to keep

I"m in a 12 team keeper league. We keep 5 players only one of which can be a QB. I havn't been keeping a QB the last couple years because I have so many young studs, but there are 6 I want to keep and only 5 I can.

WR Larry Fitzgerald
WR Randy Moss
WR Calvin Johnson
RB Frank Gore
RB Chris Johnson
RB Adrian Peterson

I also have Jason Witten, but I'm not sure I can convice myself to keep him over these otehr guys.

Basic scoring for those positions is 6 pts for all TD's and 1pt/10 yards for QB, RB, WR, and TE

THanks for the suggestions.