I think it depends. I am not planning on saving a ton of money, but it will pay for itself and then some.
Some of the counter service options can run between $12 - $16.00. The snack credits can be used for muffins, danishes, etc. for breakfast (enough for my family). For me, just having it paid for in advance, and knowing what my food budget (for the most part) will be is great. I must have at least 2 cups of coffee a day before heading to the parks so the refillable mug is a must!
This time, I have enough of my Disney Visa rewards points to pay for the plan for almost my entire stay.