The base of the litter robot is the heart and brains of the operation. The design has issues so much so that I had order my second base in 2 years time as I have 3 litter robots. Two of them have broken down and although I send one back to Quebec for repair it started to malfunction again about 3 months later. The cost of sending and repair, when no longer under warranty, was about C$200 and I found it easier to order a new base, especially since the base could not be repaired without paying another $200. If there is another breakdown then I will stop using this product. The idea of the Litter robot is good but especially the main floor sensor is flawed. After ordering the base the delivery has been prompt but the fact that I had to pay almost C$1000 in the last 2 years, on top of the price for the 2 new litter robots, makes me rate this product as unsatisfactory.