The cat is really big and heavy, thus it is very firm and does not slip each time subtracting a post-it. I find it works well made and sturdy. Neither could I detect defects nor the cat has been first dents, and where there is already quite well going gets messy at my desk.
I personally like it very much, precisely because it brings easy times fresh air into the office. The post-its can be easily and quickly insert and just as easy to remove. However, it must give the Z-Notes (since which can just always wriggle out of the paws), which are, unfortunately, a bit more expensive than the normal post-its.
My conclusion: The cat sits stably on table and works just fine. I love you just always a pleasure.