Funny you should ask--I've just been going through our last 3 trips' worth of dining receipts to determine what our average cost per day of food was. It's not as bad as it sounds--I kept great journals of the trips, so it was just a matter of recompiling data. Okay, it's as bad as it sounds--I'm a total geek.
12/04 (no DDP) we averaged $101.82 per day on food, with 13 TS meals over 17 days. We were on property 10 days (5 Pop, 5 Poly) and off property 7 days.
12/05 (no DDP) we averaged $106.58 per day on food, with 8 TS meals over 10 days. We were at CBR.
8/06 (free DDP) we would have averaged $111.94 per day on the cost of the DDP + our OOP expenses (glow cube drinks, adults beverages, etc.), with 10 TS meals over 10 days. However, we averaged $190.38 per day worth of food--a great deal. We were at POFQ.
Were our family still 2A/2C, I would definitely be willing to pay for the DDP. But my dd turns 10 in a few weeks, and will enter that 'tween land where I'm not sure whether she'll eat her $$ worth. Add that to the fact that I'm a vegetarian (and therefore always order the cheapest thing on the menu) and it probably would not be a great deal for us. That isn't to say we couldn't still save $$, because I'm way too geeky to not to get our $$ worth, but I think without the DDP we could eat well for less $$ and less worry about who's allowed to order what off of which menus.