I immediately bought the 36mm version to be on the safe side (although this is greatly exaggerated according to the article information).
My assembled system weighs between 1.5 and 2 kg and it holds snugly. Even in inclined positions with a large macro lens.
However, I definitely doubt that the head can even hold a weight of 16 kg approximately firmly and stably!
(Giving figures of 16 kg is simply ridiculous - I would like to know what kind of cameras and lenses these are that weigh such a weight in the first place...)

The adjustment is smooth and smooth - both in the panoramic axle and at the ball joint. With the locking screw, the ball joint can be adjusted more firmly and smoothly.
However, to adjust the panoramic axle, the corresponding locking screw must be fully opened - 2 full turns - otherwise it scratches or snags in places and that cannot be good for the material/ durability.
The round leveling dragonfly on the record holder is definitely useful and better than what I've had in my hands before.
However, it is better to use the camera's own leveling or other options, especially when taking panoramic shots.

The workmanship is rock solid.
If there are long-term problems, I will adjust my rating.
After taking around 2000 macro shots so far with extensive adjustment of the head, everything still works as it did at the beginning.

I'm really happy with the part. It is worlds better than my previous, jerky 3-axis tripod head from Walimex.
The K&F here is absolutely worth the money!