Why are some so critical of him, or anyone? If you think most people posting on here don't have biases, you're dreaming.
Personally, I think all the candidates at 10 have deficiencies. So, what Fatprop said is true - you pick whoever and work around their shortcomings. I'm guessing they'll all get some time. Then we'll have the debate about who else played with whoever and how that was unfair on player X, who had to play with player Y who is crappier than player Z and so on.
I think Foley has benefitted from being generally fit, reliable enough without being spectacular usually, while others have been more mercurial, with greater variances in form, and indeed fitness (yes, Cooper etc.).
We are not so lucky as NZ who have often had several very good 10s to choose from; hell, usually plenty of good players in every position.
I also agree that whether we win or lose the RWC (as a middle ranked team) will depend far more on what the forwards do, than the backs. I think there will be enough firepower in the backs to score points if we get good ball.