This is a subjective question.
If you want a higher level of service, amenities such as robes and turndown service, a private lounge with private check-in, and the sunrise/sunset safari's which are additional charges, and are willing to pay extra for this, then sure, go for it!
If you are looking for a mealplan, then no, you will not get your monies worth. Yes, it will save you on breakfast, but the fare is continental, no hot food unless you count toast or instant oatmeal. There is no lunch served, afternoon snacks are gummy worms and gold fish. The AKL does have tea time in the later afternoon with some tea cakes, but again, these are not a meal. At dinner there are one or two hot appetizers as well as cheese and crackers and veggies with dip, but again, appetizers, not a meal.
Additionally in order to partake of the offerings, you have to be there. Many don't like to take time from the parks to return. If you don't usually return to your resort to freshen up before dinner, than this is not going to work for you.
Concierge is a service, not a meal plan. Of you don't mind paying for service, than go for it. If you think it's going to save you money, you'll be disappointed.
Anne