Well, I'm a little late to this discussion, but put us down for a family of votes FOR a dinette. Our dinette provides 4 additional seat belted positions, allowed the kids to have snacks & play games while travelling down the road, or to work on homework assignments/whatever while travelling. VERY utilitarian, and then they slept on it at night.
Comfort? Not the best, but everything is a compromise. For us, the dinette along with two sofas in the living area of our class A have been an awesome combination for our family over the past 15 years.
~Rick