I hate to disagree, but from what I've seen I'd say Foles has been one of the worst white QBs this year. Part of this has to do with the excellence from so many other white QBs, but Foles has missed way to many throws and as a whole played average at best.
Foles makes some superb throws but has been error prone this season. I've said all along that Matt Barkley can run the Philly offense better. Who knows if he'll get a chance but I would take him in a heartbeat over Sanchez, and also over Foles.