I tried it. Nope, didn't work. The concept was good but that's about it. Two problems. First, I couldn't mount them directly to a stud so I used the anchors they provided into the drywall. With the 5B hanging on it you could see the top anchor start to pull away from the wall. If you mount these into a ceiling it would handle the weight with no problem but because I mounted them sideways I was pulling on the top anchor.
Second problem (as if you could live with the first problem) is that it was almost impossible to adjust the arm and keep it where you wanted it. I was trying to point the speaker down and then at an angle from the down position. The ball in the mount would always give a bit regardless of how hard I tightened it.
It was worth a shot but I'm returning them. My quest to find something that will work continues.
Joe
If you can't have fun doing it, it's probably not worth doing.