Thanks everyone. We decided against it, for now. It would be worth it if we planned on doing a lot more character meals, but as it stands we only have two planned and we really don't eat much. We all eat breakfast pretty quickly after waking in the morning, so we'll eat in the camper for breakfast. Usually one counter service meal and a treat (mickey bar, etc) takes care of us until evening, when we snack on something again.
We also know that we all tend to not get hungry at the same time at the parks so someone is always picking up something along the way. Turkey legs, fries, etc. By the time we got to our ADRs, someone is going to either be not hungry or desperately starved and cranky. ADRs would basically put us on a schedule rather than a plan and knowing my family on vacation, we're better off with a plan and not a tight schedule.
Thanks for the advice! One day if dh and I ever go to WDW on our own, you bet I'll be getting the dining plan! YAY!