Start/sit question for dynasty

I drafted Raheem Mostert to be my flex starter. I have Drake as my RB1. I need help with my RB2 and flex spots. I took Antonio Gibson at the end of the first round in my rookie draft that I have now promoted from my taxi.

Pick 2 to start: Le’veon Bell, Raheem Mostert, Antonio Gibson, Chris Thompson

Full PPR.

Thanks Guys!

It’s between Bell and Mostert for me. Bell definitely catches a lot of balls, or he used to, but Mostert has a better matchup. Everything coming out of Jets camp is making me nervous about Bell’s production this year. I think I would play Mostert against Arizona over Bell against Buffalo, a great defense. SF vs Arizona should be a great game.

Drake, Mostert, Bell for me.