Does the Ultrasonic Faux Wood Grain Oil Diffuser also humidify the room?
Yes, it produces a cool mist from water, so it adds some humidity as it diffuses your oils. It is still mainly an aromatherapy diffuser, but that extra moisture can be welcome in drier rooms.
What is the main practical benefit of the 500 mL tank?
A larger tank means fewer refills and longer sessions. That is handy if you want to run the diffuser through an evening without topping it up.
Is this diffuser mainly decorative or functional?
It is both. The flower-shaped design and light make it decorative, but the larger tank, quiet running and automatic shut-off are the details that matter in daily use.