Cheap, that's for sure. Pretty bad, it is also certain.
The problem seems to lie in Millenium catastrophic quality monitoring. It may fall on the good but also for the same product, very bad. I experienced on microphone stands. The same reference may be steady as not. A clamp proves effective and then, on the same model, quite ineffective.
Well, you can perspective: an acoustic guitar quietly put on at home will not risk much.