Low-end
Although my screen is well below the weight supported, the arm cannot support it in the up position (even when tightening the screw to the maximum), it falls back to an almost horizontal position (5° above). Once I pass under the horizontal threshold the arm supports the position better.
Turning the assembly on both axes of the arm (from the desk mount to the adjustable arm, and from the arm to the screen) is not as easy as I would like (I adjust the screen in 2 very different positions once a day). The front/back tilt adjustment at the screen was by default so loose that the screen tilted forward the first time (watch out for this when assembling). Once tightened enough it is very difficult to adjust the tilt.
The whole thing is a bit springy and the "movement/shocks" in the desk are transferred and amplified on the screen.