This book had a lot of interesting factoids about Trump and I do think it makes an interesting case about his psychology. I definitely learnt a lot more about the inner workings of the Trump administration from this book.
However, and I must preface this by saying that I'm a leftist and I hate Trump's guts, I did feel that some of the criticism in this book was unfair. There were moments where the "criticism" was so petty that I finally felt like I could understand why so many right wingers characterize liberals as self-righteous snobs. I think part of this was due to the tone of the audiobook narrator, which I perceived to be somewhat smug, but one moment that really stuck out to me was the mention of an incident where Trump got into a fire engine that visited the whitehouse and said "show me the fire, I'll put it out real fast." This incident was pointed out as an example of his immaturity which I think is, to be blunt, stupid. If Obama had done that people would have called it charming and funny, (and they'd be right to.) Similarly, I don't care if Trump likes to drink diet coke.
In conclusion, this book is at its best when it's critiquing the (numerous) instances of Trump being legitimately dangerous in his callousness and impulsivity, but it's at its worst when it's being prissy because the fascist enjoys his steak well done.