Not bad at all!
I love this kind of puzzle and this one is especially good as I’ve never seen one ad. Usually I’ll pay the few bucks to go ad-free but ads have been gloriously absent from the start so it’s not come up. The package I’m at now will require a very modest investment if I’m to gain access, which of course I’ll do. The only quibble is the levels thus far haven’t increased in difficulty as much as I would have liked. The more challenging it becomes the more engaged I become.