7850 or 6870s in CF?

So heres the deal, I own one 6870 and I'm getting ready to upgrade. My plan was to wait until the 8000 cards come out but seeing how AMD says they won't be here for awhile I'm saying hell with it and I'm going to pull the trigger and not worry about it. My question is would it be better to go with a single 7850/70 or get another 6870? I'm not really a fan of crossfire or SLi, but it seems like the better option for me. I also run 3 monitors and would like to run eyefinity on the newer games. Thoughts?

 

Heres the build I'm shooting for.

http://pcpartpicker.com/p/P2cp

I would go for a single 7850 in your position. CF has its problems. 

Yea thats why I was considering the 7850 instead of the CF.