Old enough to quit trying to convince anyone of anything; however:
If I still owned a Chevrolet 235 6 cylinder, it would immediately (assuming no clearance issues) be equipped with a triple manifold and three Carter type W-0 carburetors from a Willys Jeep identification number 636s. Linkage would be straight, never progressive.
i wouldn't personally use a dual manifold on my own Chevrolet 235 6 cylinder, but if I was forced into a comparison test; I would use two Carter type W-1 (either a mix or match 483s, 574s or two matched 420s) carbs with straight linkage. Joe has proved what two Carter W-1 carbs can do.
The bottom line is: if the owner is happy with his/her set-up..................................................................then the owner is happy.
Jon