So far I have bought 6 pieces, 3 for the house and 3 for the country house.
One of them makes noise at all intensity levels, a metallic hit as if it hits somewhere.
In terms of construction quality, it's okay without being anything special.
Attention is needed for the lamp cover as it is glass and very easy to break if screwed too tightly.
For its price, it is a decent choice as long as it is not a defective piece and makes noise.
Under normal conditions, it is quiet on the first level, tolerable on the second level, and quite audible on the third level.
Last year, it was tested in heatwaves and performed well.

I bought two. Completely silent even on the highest setting. You can sleep comfortably at night.
It is not very powerful and doesn't produce much heat. It is suitable for small spaces. Up to 20 - 25 square meters.

Average things - you get what you pay for.
On the third setting for the night, it cools a little - but it makes a lot of noise.

It's not suitable for a bedroom if you're a light sleeper.
I have it in a bedroom on the top floor and it works slowly only at night, because the panel burns!