Except for trying to get the cover off to unwrap the plastic on the filter (the plastic was wedged in the mechanism-- not fun!), it works straight out of the box. There is a lot less hair in the living room, too.
Two suggestions:
1. make a bigger one. This one will do my living room, but the rest of the house, no.
2. Make washable filters to reduce on waste and offer a spare for purchase.
Otherwise, like the PetSnowy litter box, a very wise investment.