If they still have this kind of special locking lugs I'd say that they are very proprietary.
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It might be better, it might be worse, I cannot speak to the technology...
The selling argument for the Verney Carron action, which is nothing but the Demas action (Verney Carron purchased Demas in 2004) is to have 3 lugs. On the surface, 3 lugs sounds stronger than 2 lugs, right?
The reality however, is that the Demas/Verney Carron 3 lugs action is not wider nor heavier than any classic 2 lugs action, therefore the question becomes: what is bigger: 2x3 or 3x2? What I mean is that there is no transcendental difference in bearing surfaces or material strength between a 3 lugs action and a 2 lugs action of similar dimensions and mass, it is just that the approximately same material mass is divided in 2 bigger lugs or 3 smaller lugs... In any case, if there is a quantum leap in strength, it failed to be revealed by various tests and it failed to catch wide interest...
Post WWII Verney Carron reached a certain proeminence in France by introducing the Sagittaire, the first mass-produced French over-and-under shotgun, in 1966. And a good shotgun it was. I remember my youth in the French Alps, anyone who could afford one got one. I actually learned shotgunning on one and have fond memories. No amount of snow, ice, sleet, dust, mud, or banging on rocks could prevent a Sagittaire from closing, going bang, downing a brace of chukars, opening, ejecting, and doing it again, and again, and again...
Verney Carron has on and off teetered on the verge of financial solvability for many decades. It was first saved in the 1980's by a large military contract to manufacture parts for the FAMAS French bullpup 5.56 military issue rifle - and a good rifle this too was - and this contract allowed the retooling of the company and the subsidizing of the development of new civilian rifles and shotguns, including a light weight alloy receiver Sagittaire that was quite successful.
There is no question regarding the quality of the rifles and shotguns produced by L'Atelier Verney-Carron Demas Artisan in the last two decades but there have been recurring questions about its economic viability. I guess that the response has been provided, sadly...