Sit or start, Caddy? or Visanthe?

So after last night's 49ers/Bears game, I have a little ground to make up. I started Crabtree and Forte, and in my league, it got me a total 22.5 points combined from the two. My buddy that I played against, started Frank Gore and Greg Olsen, and that got him a combine 27.5 points from the two. I need your opinion on who I should Sit/Start to do a little catch up. Should I start Cadillac Williams, who is regarded as the main running back from Tampa Bay going up against Miami. Or Visanthe Shiancoe, who is just one of the many weapons from the Minnesota offense, but is playing against the lowly Detroit Lions?