We used the DP counter service on this trip we just came back from.
There are a couple things to consider about the DP (in my opinion).
Whether or not the DP is "worth it", is up to the individual.
The ease and convenience of the DP while one is doing Disney is wonderful, particularly if your doing Disney commando style. You can keep moving along, no fuss, just stop and eat (or snack) where you are at, then keep moving.
However, getting your $money worth$ outta the DP is a whole other story.
Disney counts on most people not leaving the parks to go eat. If you are try'n to get the equal amount (or more) of money out of the DP that you spent per person per day, then you will have to do a little planning on where you choose to eat and most likely will have to leave the parks for a period of time to do this. All of this can cut into your park/play time at Disney.
In my opinion, the counter service DP works best for us cause we like to go to the F&W fest and use the "snacks" at the food kiosk at Epcot around the World Showcase. (which makes the cc/DP so more worth it)
Because of the type of life style that my beautiful bride and I live, leaving the parks to eat (and then returning) really isn't a problem for us.
So, "worth it" and "gett'n your money worth" are pretty much two different things and up to the individual.