Yes, state of the art is better. With one caveat, only if the cylinder or control valve have check valves to hold the cylinder in position, after the length change is made.
Otherwise the cylinder will likely change length due to leakage in the control valve. Which is common.
So without check valves, the mechanical adjustment may be superior, as it will hold position forever, in practical terms...
And what of shock loads on the cylinders? Do the check valves adequately protect against that? I have been interested in adding at least a hydraulic top link, but worry about that. Unfortunately, I did not get rear remotes on my L2501, although I could make do with my 3rd function for a hydraulic top link controller. So I am just thinking about things at this point.
But, back on topic. Retired Plumber, I agree. My 45 year old John Deer has one and it works great, and yet Kubota has that awful thing that is a pain to turn. Granted, I rarely use my 3 point as I keep the backhoe on mostly. I used the box blade the other day, and adjusted the angle for sloping the soil. It is aggravating.
Here is an alternative for you that I am considering doing. The place that sells the leveling box even sells the appropriate bushing that the guy in the video uses to modify the leveler box.
