I have been fascinated with the Boss "stub rib" for some time. They were able to take quite a bit of weight out of the barrels with the short rib. I don't have an example, but am on the lookout for one. My Green O/U is completely ribless, but with the lugs below the barrels, the action is taller and the arrangement works beautifully from a functional, if not aesthetic one. It is my most deadly game gun despite being 106 years old. Unfortunately I am not able to comment on the stub rib sight plane...yet.
One hand carry through the uplands is smooth with the Ribless design. I can imagine it being satisfactory with the stub. To me it is uncomfortable with a level file cut example.
