Eddie keeps talking about the smash and grab at the WC. I am sure he doesn't expect to win the thing but he wants a really good showing with a chance to cause some upsets. I don't think he wants a steady limp through the group stages and honorable loss in the quarters.
To cause some big upsets he will need a 10 who can break open defenses. QC (Quade Cooper) has that potential, he can do the sublime and the ridiculous.
Foley on the other hand is Mister steady, won't make many mistakes but is very unlikely to throw up the cutout pass the parts the red sea.
If Eddie is looking for an attacking 10 who might do something spectacular then I think QC (Quade Cooper) backed by Carter is the way to go. If Eddie wants steady then Foley back by Noah seems likely.
Personally, I would rather Eddie be brave and go out swinging, it may end badly but it will be fun.