Just want to start off by saying I'm pleased with the product. I'm using it for a fixed small PA I'm using in my studio/rehearsal space to save floor space. I used to have then slanted on the floor.
It was a little tedious to assemble, but I guess I'll only do it once.
All the materials feel very sturdy and well made.It does have possibilities to adjust the angle which is great, I can still angle the speaker slightly since it sits on the flange, but it could've been nice to have the option to angle the arm as well. But I guess that would compromise the stability. The only real negative think (for my purpose) is that the arm is longer than I needed and the speaker sits further out from the wall than it has to as it's not that deep. The flange thickness is adjustable so I could tighten it once the speaker was in place and I will never turn or anything.
All in all, great reliable product. K&M has great products. It's German.