I've got a couple and tbh I like them.
The slider bracket is firm and grips well, however, even though they can be slid anywhere on the top ring frame, there are only two vertical positions the bracket can be used in - 90degrees to the net top, and in line with the net top, there's no other adjustment. So ideally they need to be used with a bar fixed to the legs of a platform.
My only gripe though is that the nets float despite being used several times. A couple of ounces of lead on each one keep them down.
I did notice that the end rings seemed to hold water as well - not good in my opinion from a disease prevention point of view if that's the case.
so far so good - although i did have a slider bracket go on the non-sliding part of the bracket - very promptly replaced by MAP/Benwicks. Agree with Dave - that the weighted bottom rings seem to float and require l/net to push out and down.