For me, there is 1 big design problem, 1 other small, 2 bp related to my particular case, and a lot of quality.
The design problem is: the base (the lisaison between the foot and the base) only allows 180 ° rotation!
My office is not pressed against a wall, I wish I could do "backward from" the first part of the foot (thus beyond the office about 20 cm) then do "back to front" ( and possibly not completely) the upper arm.
Which would have allowed me to have my screen was floating just above the base (and not 10 or 15cm in front as at present) or even beyond the office.
As designed, the foot only allows to bring the screen (relative to the base), no away !! It's really a shame.
The small pb design, it is the system to keep cables in the upper arm: there was just 2 brackets (top and bottom of the upper arm), and I not go into details but c is not really effective if you often move your arm. But it is not seen very important that anyway if you move your arm bcp you need "bcp soft" and therefore ultimately leave them free cables at this level (and enter them into the sheath palstique of the lower arm) is fine.
And regarding my "characters problems," they cocnernent the fact that I have a 29 "screen ultra wide (extremely large) and yet very lightweight (4kg I think I might check if necessary).
The good news is that although the weight is below the announced minimum weight, it works anyway super good, but not quite either (in particular, I can not really use the 5 ° tilt "towards the low "returns to the screen 90 ° alone, the spring being a little too powerful ...).
Good, but it is mostly a quality that is finally so effective even if I'm not in the normal utilisaiton limits.
Finally, if the foot is designed for heavy screen so large a priori, it is a bit small for my 29 "UW: in particular, I can not turn the screen vertically without tilting a bit.
Well, again I not take away a star, because it is true that a 29 "screen vertically UW is not really useful anyway ...
Now you know everything. It would be to do again, for my particular situation, I may be taken Humanscale M2 (which I have to work) ... But the Ergotron MX has the enormous advantage of providing two basic types of fasteners ( "clamp" desktop board or screws through the office) while the humanscale, choose.
But in general, this one is excellent (and plus it was cheaper).