As someone who commutes to rehearsals and gigs, light weight is an important factor for me, and this delivers nicely without sacrificing reliability.
I was curious about single-brace vs double-brace, so I compared this against a pretty standard single-braced X-stand I have (can't remember the brand/price, but definitely on the cheaper side), and yeah, this double-braced one is so much more stable, even with its light weight.
While playing a 61-key keyboard at standing height (where any X stand starts to become a bit narrow), there's still a tiny bit of horizontal wobble, but it's like 5 times less wobble than the single-braced. During rehearsals and gigs where my concentration is on playing, I don't even notice the wobble.
It would probably be even more stable at sitting height or for shorter keyboards, but I don't know for sure how it would fare with longer keyboards when set tall for standing play.
I also tested against a KS-4000 with the same setup (standing height, 61-key), and I'd say the KS was even more stable, plus other advantages like not having to trade off height vs. width, but this K&M was also perfectly fine on-stage.