Great deodorizing, but noise
I would love to give this five stars. It definitely gets five for deodorizing in the space that I have it - a bedroom where the cat's litter box is. But after having it for a couple of months, it is now quite noisy. At first, it was just a low hum, but now I can hear it in other parts of the house.  Not sure what to do since it works great, but I can hear it at night when I'm trying to sleep in the next room.
Rating: 3 stars