Question about Duux Ovi

According to my research, the humidifiers use different technologies. The Duux Ovi is a self-regulating cold water evaporator that distributes the humidity in the room by means of a fan through a filter. As soon as the humidity rises, the water vapour output decreases naturally. The Duux DXHU15 Tag Ultrasonic, on the other hand, is the more powerful humidifier based on ultrasonic technology. Through vibrations, it silently transforms water into visible mist. In addition, the Duux DXHU15 Tag Ultrasonic has a removable water tank with a capacity of 2.5 litres for up to 10 hours of continuous operation. While the Duux Ovi is equipped with a permanently installed 2 litre water tank incl. aromatherapy bowl.