Great team. I think Foster and McCoy are the two best backs this year. I'd stick with them as I'm sure you've been doing.
At receiver I'd start Steve Smith and Colston, they've got great matchups. The only thing I'd worry about is Cam running for three TDs, if you are worried, I'd go VJax. SD has been unstoppable in December and he's by far the best receiver. Thomas is great, but it's Tebow's arm and an only recently hot receiver. I'd stay away from Steeler receivers if given the option.
At flex I'd go Mendy. He plays better at home, and will probably get a lot of carries regardless of whether Big Ben starts or not, but pretty unreliable overall but I could see him getting 2 TDs easily. VJax is also a great option, a little more all or nothing but if he's been helping you in PPR than i'd do it.
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