Good, but not great if you have multiple cats
I have four cats, and found that the most skilled cat was able to get the treats from any part of the board in seconds, and so was eating nearly all of the treats herself. I also discovered one of my cats couldn't really work it out/was too lazy to try and just sat by the board waiting for me to give him treats instead.
I think it's a great toy if you have one cat, or your cats are similar in intelligence, but otherwise you have to be really careful in monitoring which cats are eating the treats!