10/10
Only day 1 I have had it but within 2 seconds of installation my 1/2 cat's used it. It is very easy to install and use. The app is very helpful to determine which cat has used it as there is a scale that can help you determine that as long as you know your own cats weight. After the cat uses the device, you can also change how many mins of self cleaning which is VERY quiet. The price is worth every penny.