I found this book accessible and interesting mainly for beginners looking at career and vocational purpose through the lens of astrology. It's cookbook style, so you're going to learn less about integrating the information in your chart (there are a few suggestions, but not much depth) than individual descriptions of your personal placements.
I wouldn't recommend for astrologers. The "Cosmic Calling Formula" isn't an innovative tool, just sun / moon / AC / MC with topic-specific descriptions, and some may disagree with the framing (of the AC in particular). These are introduced well for newbies, but there's nothing extra on the art of interpreting in a career context or how these elements of career might fit together practically.
For newbies, there's a LOT packed in: after the four key placements, Walstein covers all the planets, the nodes, Chiron, and Pallas Athena. Looking up your placements can be really fun, but also potentially confusing. There's a risk of over-emphasizing planets and points, especially since personal vs. outer planets aren't broken down. The descriptions themselves vary—for example, I found the take on Moon and Mars placements really useful and on point, while the Venus descriptions honestly confused me. Nothing super off or harmful, but if you're considering this book as someone without astrology knowledge just be open to the fact that there are other interpretations! Some house keywords are limiting, and in some places there's maybe an overemphasis on interpreting a sign as what you want to create for others vs. how/what you create independently.
The beauty of this book as a tool is in pulling together all the information about your own chart, considering it together, asking yourself what resonates, and doing some self-exploration guided by what you've synthesized. Thinking about your core identity vs. the impact you want to make on the world vs. what you need in a work environment vs. what motivates you, for example, is a really interesting exercise!
[ARC provided by Edelweiss.]