I play standing up so usually I need to set my stand at around 90 cm height, and I am also currently using a 61-key keyboard. I've compared this stand in this setup against a single-braced X-stand and a double-braced (aluminium) X-stand, and the KS-4000 comes up at the top in almost every regard.
This stand had the best stability out of the three, with almost non-existent horizontal wobble.
It is also very useful that this one can go both wide AND tall (the X stands start to become a bit narrow at that height for my keyboard).
It is lighter than most other scissor/accordion stands (the Adam Hall SKS 05 is lighter, but doesn't go as tall as I need), and is quite compact when folded. No tools are needed to set up or collapse. (For the height, remember to pull the pins after unscrewing!)
The scissor design leaves space underneath for pedals, which is typically a problem with X-stands.
I have a K&M 18997 (double-braced aluminium), and only advantage of that one that it's lighter in weight. So it's a bit easier to commute with, but not by much.
In every other regard, the KS-4000 is the best stand I've tried. Only desk stands and Z-stands are probably even more stable, but they're also heavier, more expensive, and/or not high enough for standing play.
People should just skip over X-stands and straight onto this one!