I used the Venta LW 45 since now nearly 10 years and am very satisfied. Especially during the heating season, it provides excellent results. I love indoor plants of all kinds Customised bonsai, the plant went without the Venta always bad if too little moisture in the apartment was. Even the floor creaks and squeaks since he no longer is in operation. We have a ca 20 sqm living room and I built the following rule of thumb on. Since I am very sensitive to noise, I have a switch on the Venta. At night he goes then for 3 hours at level 1 and the water content is sufficient for approximately one week. Depending on how humid the air is. I like that about this device, it does not spread just keeps moisture, but the stack of plates adapt depending on the level of interest. I occasionally use water kalfreies recommend, because the lime in. Tap water wears the Venta considerably.