Who should I play WR, Flex HELP!?

I have and am playing Wes Welker for sure, but I'm indecisive about my WR2 and Flex spot WR/RB. I've got Roy Williams, Brandon Marshall, Eddie Royal, and Reggie Bush to choose from for those 2 spots. Also have Josh Morgan and Earl Bennet, but theyre more unlikely to produce but also have sleeper potential ... Popular vote on starting Marshall period, but he's had no playing time so far ... Thoughts?