Realistically, the Deluxe plan gives you as much table service dining as you can handle. While the
DDP includes 1 table-restaurant meal per day, and 1 counter-service meal per day, the deluxe gives you 3 meals per day, that you can use for table or conterservice.
Additionally, the deluxe plan gives you more snacks (2 versus 1), the refillable soda mug, plus an appetizer with lunch and dinner. (Except for some prix fixe menus, you do not get appetiziers on the basic plan).
The upgrade cost is about $30-$35 per day. (If you are upgrading during peak season, I believe it is about $30 per day).
If you want and actually get all the "extra" food you are entitled to -- appetizers with every meal, all your snacks, 3 sit-down meals per day, then it easily pays for itself.
But I would think that is way too much food for most people. Still, it will likely pay for itself if you like to do a lot of signature dining (2 ts credits), and if you prefer table-service restaurants to counter service, and you want to use at least some of the appetizers and snacks.
For example, during peak season in 2011, the DDP is $48, and the DxDP is about 78.
Let's say a "typical" DDP ran like this:
Cereal & Milk snack credit breakfast (worth about $3). Juice/coffee out of pocket ($2 out of pocket).
CS lunch -- Approximate $14 value.
TS dinner -- middle priced entree, dessert, beverage, no appetizer -- Value about $35
So cost was $48 for DDP during peak season, plus $2 for morning beverage, or about $50 in cost, to get $52 "worth" of food.
For me, a typical deluxe day may go like this:
Counterservice breakfast -- Value, about $8
Table service lunch -- soup or salad appetizer, middle priced entree, skip dessert -- Value about $25
Mid-day snack plus mid-day beverage (use of 2 snack credits) -- value about $6
Dinner-- including appetizer, middle priced entree and dessert -- About $43
Value-- About $82, at a cost of $78 -- And that was without "maximizing" use of the credits. With more expensive entrees and appetizers, without skipping dessert, and especially if had done TS breakfast instead of CS, could easily have been $100+ in value.