Sounds like an interesting book, though far too many pages for a subject I have only a passing interest in. I would note given the authors affiliations I'm not sure I would ever consider it something that could "set the record straight". If there's a controversy about the program the authors backgrounds don't exactly suggest one will be getting a balanced view. Perhaps I'm wrong, but I appreciate the suggestion anyway.
It’s not at all unbiased, in a journalistic sense, and doesn’t present itself as such (for others: it is written by the now retired program manager of the F-35 development program). But the relevant facts about the performance and cost effectiveness of the plane are a matter of public record, and the book is interesting for providing the inside view on the politics which resulted in the unfair propaganda campaign against it.
You are free to draw your own conclusions of course. I worked for Lockheed previously in my career, and some in my family still do. Though I hold no stock or other ties now (different career, different industry), my experience does lead me to take the authors at face value. There are many issues with Lockheed leadership, but professional integrity is not one of them.