It's good— But not for its intended purpose
My cat isn’t interested in the “sensory” aspect, so instead I’ve used it as a treat toy.
The brush part is easy to stick treats into, and they come out easily, but the best part is the white grooves at the front. The treats get stuck in there really well and it can take her all day to lick, bite, and pull them out.
The only annoying thing is the grey base. It doesn’t keep the toy in place at all and is completely useless. My cat has knocked it over several times while using it.