I've bought this to use with the main Gravity keyboard stand. It was subected to some heavy use - I'm a gigging musician - but on the 4th or 5th venue the roadie came up to me with a jarred face, stand in one hand and the thin rod in another: it had broken in the connecting nut.
Fortunately, it doesn't interfere with the abiity to hold the upper keyboard: I believe it's just a maximum-lenght failsafe for not overextending it.
Another minor gripe: although there are markings on the stand for tilt - great! - these just have a "broad" alignment with each other.
So, all in all, beware of how you treat it, I can't endorse it for road-heavy use.