I bought a couple of these a month or so ago, along with a couple of other things. Had to try one out right away, and it really does work :-D Set up was easy, the knob works as advertised, and it has been stable ever since. The non-stick pad is a great addition, too. Right now, I am using one of them to hold my external CD drive, and a couple of portable music players. The tray gets bounced a bit, as a result, but it has been solid the whole time. I gave the other one to my wife, but it would not work with her work-from-home set-up, so she put it on our TV screen, where the remotes and such now sit: perfect! The pad, however, she did keep, for her pens, which tended to slide off her workstation, which is tilted a bit for ergonomic reasons. So, it all has worked out beautifully! Definitely recommend these and will consider buying more for gifts.