Love the Deluxe plan but don't always use, DW and I always use it when doing the big family trip in may as we can do the 'Spirit of Aloha', CRT and other signature dining events which for us are just as important as touring the parks.
Example Aloha is approx $80/pp before discounts (AP/
DVC/DV/TiW) so figure a check north of $400 for 4 before you are done and thats ONE meal, So with the deluxe plan we can have a TS lunch or Character breakfast and have the event as well for approx $320/day for all of us (Plus snacks and free drinks at resort)
Don't get me wrong this is a LOT of money but if you are staying on property Disney food is expensive with a capital E and there is generally a small delta from least to most expensive items on menu.
We are DVC and usually stay in a 1BR so we have full kitchen for breakfast, etc and we generally have Garden Grocer supply us with breakfast items.
You really need to look at what you want to do at Disney and plan accordingly but dont make the mistake that many do and think they can 'order the cheapest item' when mac-n-cheese is $11.95 and a steak is $ 17.95 'and and and' things add up quickly.
When we do a quick weekend getaway we usually use the regular dining plan as in these cases we want more park time and usually snack our way through the day.
If you have a AP you can get a TiW card for $75 and you will break even at 350 in food spending and save about 20% after that. One advantage of a AP is that you get discounts of 10-20% on merchandise just about everywhere so if you buy a lot of Disney Stuff you will benefit there, And there are discounted room rates for AP holders as well, I've had offers for the Value's as low as $39/night.