It is sturdy, stable, and can hold perfectly a Studiologic SL990 of 20 kg. The height is just fine, in the minimum position where one can block the legs with the 4 screws this way comes on 75 cm from the ground level to the keys top in my case. If you do not use those 4 screws, you can lower an additional 3 cm. Anyway lower than an actual piano, so unless your keyboard is not particularly huge [in height], you can have a comfortable hight setting.
The only issue are those screws which hold together the extension of the two lateral parts. Those are disposed "looking" downwards at almost the middle of the stand. And in my case, I repeatedly hit my kneecap in them each time I sit down to play. One solution would be to throw away one screw, and the stand is stable, because the other screw holds the distal tube. Another solution would be to throw away the above mentioned screw and get a power drill, and drill a horizontal hole through the external quadratic tube and the internal inox tube, and put a regular screwer holding everything together. Obviously who designed this stand was somebody who never played any keyboard on the prototype or was a short person, or used a higher position of the stand. A suggestion [for the designer] would be to place those 2 screws in horizontal, facing each other, and not downwards. This way it doesn't bother anyone's knee [who is tall], and also much easier to put together.