The Philadelphia Eagles have an interesting situation on their hands. Michael Vick (the opening day starter of the Eagles) is injured and he won't be back on the field for a couple more weeks and in his absence the Eagles have started Nick Foles who has a much different skill set than Michael Vick. Of the two, Michael Vick is easily the better runner. While Foles is easily the better passer. So the decision comes down to how the head coach (Chip Kelly) decides to run his offense. If he wants to keep the rushing threat of Vick and LeSean McCoy on the field then he can go down that route, but if Kelly wants to have a more traditional and more balanced attack on offense then Foles is the way to go.
If it were up to me, I'd start Vick because it makes it much more difficult for defenses to prepare for the Eagles because the offensive possibilities open up for Kelly. Using Vick's athleticism Kelly can play the Option, the Wildcat, and the Pistol offenses (which are much more running based strategies) while with Foles his limitations on offense are much more traditional. Foles has his own level of athleticism, but it just doesn't compare to Vick's. Foles is the poor-man's Aaron Rodgers he has enough of an arm to make the plays he needs to make, but also has some running abilities that kick in when he's in trouble or when it's a surprise for the defense.
Don't get me wrong I wouldn't trade Foles unless the return is outstanding because we all know that Vick is bound to get hurt again. Vick's reckless when he's on the run with the ball and the defense always gets their shot at hitting him just like RG3. Keep Foles on the bench and he'll eventually get playing time. The notion of starting both shouldn't even be considered because when you have two quarterbacks you really have none.