This arm is designed for truly heavy microphones.
My assumption was that over-capacity can't be bad, and if I use smaller microphone I just get more durability.
But the springs are tuned for heavy weight, and to work for smaller microphones the arm must be loaded with included counter-weight. I have to use the counter-weight with a SM57 clone in a metal shock mount.
So in effect I have useless extra weight on my table. I would go with a smaller arm if I knew better.
The spring loaded design is great, it will never sag. The quality here is very good. The ball joint is useful to mount the microphone upright on its handle, so visibility to my computer monitor is unobstructed. The arm is super stable and easy to move. It holds for a few years already, I move it at least weekly.
A minor issue: sometimes something bangs loudly inside when lowering/rising the arm around one specific angle. As if a spring is catched and released suddenly.
A maintenance guide is missing here. The mechanism clearly needs oiling after few years. I will have to figure it out.