I struggle with this each time as well - basic DP or DxDP? Do I eat $80 worth of food/day? Probably not. But...
I've done spreadsheets which compare what we would pay on the DP + OOP costs as compared to what we would pay on the DxDP, & it basically comes down to pretty much breaking even. I look at this way --
1. I normally book more ADRs than I have credits for on the basic DP.
2. Some of those ADRs are normally at 2 TS credit locations (CRT for example).
3. W/ the basic dining plan, I'm getting a quick service meal & a TS meal/day. So, I'm still having to do something for breakfast or lunch OOP - whether I'm packing Pop Tarts to eat in the room or not, it's still OOP costs. W/ the deluxe, you get 3 meals/day - which is how my family normally eats.
4. W/ the basic dining plan, I'm only getting 1 snack/day. Usually, you're going to eat/drink at least 2 snacks per day - even if 1 of those snacks is a just a drink. W/ the deluxe, you get 2 snacks/day, so less OOP costs for snacks.
5. Additionally, w/ the deluxe, you get the refillable mugs to use at your resort.
6. Plus, DH likes having everything prepaid. In the end, we sort of look it as part of our overall "resort everything inclusive" experience instead of what we're paying to eat each day. We're Disney's favorite kind of consumers that way!
I dislike making 3 ADRs/day - just too much running from 1 restaurant to another for us & takes up too much park time. So, I probably don't get the most "value" out of the DxDP. For example, on some days for our future trip, I have 2 quick service meals planned & only 1 sit down meal planned. However, there are other days, where I have 2 sit down meals planned. On one day, I think I actually have 3 ADRs planned. However, if I had the basic DP, I would not have as many ADRs - we'll be there 8 nights, so, I think, when I was considering just getting the basic DP, I had 11 ADRs planned - 3 extra. But, DH said to go ahead & book it w/ DxDP, so I've made some extra ADRs - just because I could.
So, again, for us, after I calculated the cost of the DP/day + OOP costs, it makes more sense for us to get the DxDP.
This year, my problem is our two older children will be 11 & 10, "adults" in Disney's eyes. And I'm having a very hard time paying $80/day for them.
One thing that does need to be considered when upgrading to the DxDP - one naturally books more TS meals w/ the DxDP, &, w/ each TS meal, you get appetizers, so your OOP tip expense increases - due to both more TS meals & higher meal overall costs.
We really enjoyed the DxDP. However, like I said, I'm having a harder time this year w/ my 2 "adult" children.