We have done Disney both with and without the Dining Plan, and we love the Dining Plan!!! It is so nice to not worry about the bill when sitting down to eat dinner. We have had budget trips with a few lunchtime TS and lots of CS. They were wonderful. The cost to feed my kids as they have gotten older has gone up a lot. The downside of the Dining Plan is that my kids tastes now lean towards Filet Mignon and Rib-eye steaks. It makes our dining out at home pricier! I think the Dining Plan is a great deal, even when it isn't free (but I like it better when it is free!!!)
We lean towards TS that tends to be pricier, since most character meals don't appeal to the kids anymore. Kona, Cali Grill, Wolfgang Puck's Cafe, Le Cellier, Les Chefs and Concourse are on the schedule, as are Boma and 50's Prime Time, which are less expensive. We have the must do favorites, and each trip we try some new places. All of us get to choose dining spots. TS has become one of our favorite parts of the trip!
Every visitor and family has their own decision to make. No one answer is right for everyone. Do what works for you.