Oh no...that's not good either! We did try the MDR one night on our 4 week Wonder cruise a couple of months ago. The service was good, but we were seated next to a family with 3 screaming (and uncontrolled) young boys. Did not go back. We kept to CK the rest of the cruise, except for one attempt at Chops (total fail).
Actually it's not really the food in CK, which most times we find to be edible for us...it's the quieter and more relaxed experience we appreciate. When we book a ship that has CK, we are GS and above. Otherwise the JS on the smaller ships, with having dinner in the MDR works for us.