It works well. I use it with my Neumann U87 since the original shockmount is a couple hundred dollars. It doesn't look extremely high quality, but it does what it is supposed to do, but for under $20 I'd say it's well worth it.
Holds my Heil large diameter mic tightly and firmly in place stays where it is set and easy to change position. Does a good job of isolating the mic. from vibration on the desk