The real answer is "it depends". I've owned two mid kitchen trailers and I just traded a rear kitchen for another rear kitchen. My last RK only had a little over 8% tongue weight and towed squirrely unless I had a full tank of fresh water which was in the front of the trailer.
The current RK has nearly 13% tongue weight and tows just fine. We have never noticed any more movement of dishes in either rear kitchen but the first one had the EZ-Flex suspension and the new one has MorRyde.
If a RK was as bad as some make them out to be, there would't be so many floor plans offering them. I even had someone tell me once how badly my trailer was designed because it had a door near the back and close to the rear kitchen and I would never be able to keep my stove lit. I can say we had that trailer for 6 years and not once did the stove blow out or even become difficult to light. I just scratch my head with comments from experts who never owned one.
The bottom line is make sure there is adequate tongue weight of at least 10%+ of total weight which holds true for any trailer. Beyond that, get the floor plan you want.