I'd stand pat, depending on how many you start. If it's basic 2, 2 and a flex then no. Gore, McCoy and Foster should be fine and you have 2 solid WR to start in Colston and Smith. I think Gore beats Greene this year and Boldin misses too many games IMO
Standard Scoring, 8 Team $ League, Start...QB,QB,RB,RB,WR,WR,WR,FLEX X3,TE,K,DEF. QB- RB- WR- TE- K- DEF-
I would not do it. I really like Gore this year with his easy schedule and new O-Line. Greene was injured twice last season with limited action and will most likely be injured again this season. I don't think the upgrade to Boldin at wide receiver makes up for the downgrade at running back.