I'm not a good person to judge this book because I not only have a technical background in electronics, I also got my American Extra-level license (AC1DM) before this one, so, I had to study all this material a few months ago. This feel like a revision.
Something that really surprises me about the book is that it says the ionosphere reflects radio waves. I understand we use that word in casual speech but I believe a book on ham radio should be more strict and use the correct term: refraction.
For whatever it matters, I passed the exam with a 43 out of 45 questions answered correctly.
Well structured, easy to follow and broken down into 'worksheets'. Although more in-depth than the foundation it appears less intimidating due to the way the book is laid out. Working my way through.