I am also trying to decide on the DDP. We would probably do QS plan for a family of 4 (kids are 13) adults x 9 days. We will have a car...what are some off property eating choices? We don't mind some fast food but we like to eat a "meal" for dinner.
We have done dining plan once when it was free and once when it was not, and we will not be paying for it next trip. I did the math last time. I looked at every menu of every place we would eat, chose what I thought the three of us would choose, added tax, and ran the numbers. Dining plan worked for us on the last trip, but ONLY because we did character meals. It was a hot May last year and we felt like we were stuffing ourselves to eat food we didn't want. Since we are no longer first timers, the time we waste (arriving 15 minutes before adr, waiting 5-40 minutes for a seat, ordering, waiting, eating, waiting to pay) made me INSANE. We will select a few table service favorites for ADR's and see what happens next trip, no dining plan. I expect to come home with lots of mouse ears as I will spend my savings on memories!
The counter service plan provides the least potential savings, and the adult price (which you'd pay for your 13-year-olds) makes it a terrible value. No matter if you'd eat on-site or off, I'd skip the plan.
I would take it if it were free of course
We "create" our own pre-paid dining plan by buying a Disney gift card and loading it with the money we anticipate we will spend for food. In that way, our food is pre-paid and yet we do not feel we have to buy a drink or dessert unless we want drinks or desserts. If we have money left over then we just reuse the card on our next trip.
Kate
I agree that it is usually cheaper to pay OOP. The food and drinkis wonderful at WDW so sometimes we get the meal plan to have a wonderful, relaxing, eating vacation. I also consider how much time we want to spend eating.