I put 5 stars as overall I am satisfied with the product, it makes what it proposes.
But it needs a lot of everyday care for me. It is written in the paper that you need to clean it!! But I didn't expect I will have to fully unbuild it, wash and dry every single day...
With the water that we have (island, hard, salty), the scale inside is accumulated after EACH USE and a lot! , stucks and after some time doesn't let the steam go out if you don't clean it daily (first time it happened after 4-5 days of use and I thought it was broken. Until I opened it.. And saw like maybe at least one soup spoon salts..)! So every time I use it at night, later in the morning, I have to open and clean it. But this is what we have to expect with such a water actually... So actually no complain to the product, just don't expect it will not happen if you use a tab water.
Maybe if you put a bottled or distilled it will be better.

Summary: I use it for a baby at night. At a big room (around 30m)
Because of the air-condition we gave to use in the hot weather , the humidity drops down up to 38-40%..

+ the device makes it 43-45% in the room (no more in such a room. But already better)
+ even though I have to clean it daily, it is very easy to use (build/unbuild, etc.), just needs some time.
+ it is NOT loud for me. only a bit when it starts
+ it is not cheap but compared to the other good ones I would say it is not expensive.

- it works around 6 hours so if you start it early (22), you need to refill it during the night if you want to have it full night.
hot steam - you should consider to put it to a safe area
- of you have a salty water like me - be ready to clean it every day fully (very often also with vinegar.