Thirty years ago keyboard players would stack their second keyboard on top of something sturdy, like a 350-pound Hammond organ, or 150-pound Rhodes piano. The top keyboard (such as a clavinet or monophonic analog synthesizer) did not bounce no matter how hard you played it.
Thankfully today a 20-pound rompler [a keyboard that plays pre-recorded samples instead of generated waveforms] can replace all those old heavy keys, but I don’t like the light bouncy feel of X-type stands.
A few years ago I heard about the Standtastic series, and found it simply does not bounce. It’s as solid as granite. I bought two and keep one in our practice room and another for my gigging rig.