My cats love it.
So this is really just for people who want the kids and grandkids to brush the cat cause they will find it fun and entertaining and your cat will finally like them.  I love it.  It works like it says.  I have one long haired cat and one that is finer hair.  It works for them both.  it doesn't have to completely fill up to work.  We have had no issues at all.  I only have the cats so I don't know about how it works with dogs.
Rating: 5 stars