While the book was undoubtedly as good as others in the series, I do feel like less was actually accomplished in the same listening time. This is one of a very few series that can get away with being a bit formulaic, which is good because it’s starting to feel that way.
Reviewing the fourth book in a series can basically go like this: If you haven’t listened to it listen to the first one. If you were happy with the series until now, carry on with it.
It’s neither a shining star nor a turd, but it is in the top 4.