There's a great calculator tool on
http://seeyareelsoon.wix.com/seeyareelsoon It lets you input where you plan to eat and how you dine (lots of QS? appetizers? etc.). It even takes into account any discounts that you may be eligible for. Then it compares what you would spend on the dining plans vs. what your OOP costs would be. Just take a look at the OOP cost plus your discounted room + tickets and compare it to the cost of a
free dining package. The cheaper trip wins.
It turns out that we tend to do better by paying OOP for our meals.