Three switches and all three have the same problem. The left button usually works on the first press, the right one requires a strong press and in a specific spot, and it may or may not work! With a second or third press, it works OK. It's a shame because it's a very beautiful switch, I've bought the whole series and I can't change them. And in general, I'm not satisfied with the series, not even with the simple switches.

The keys have a strong construction with powerful key bounce springs. The durability will be shown over time.
Update 2 months later: The switch that lowers the roller broke and when pressed, it remains stuck. You have to press it in the opposite direction to stop it. Is it a material flaw or a low-quality product?