Unfortunately, for all the awesomeness that this book contains, it leaves you with the feeling that you've been lectured at.
Probably most autobiographies have the tendency to "inform the user" of how their life would be better - like mine! - if only they listened to my wise experience and changed their ways. Then everything would be marvelous and you'd never have any problems. Of course, I'm being more than a bit snarky here - and Hadfield's book has many large sections that are not about bettering yourself - that are actually about space travel itself! - but in the end I have a bad flavor in my mouth from reading the book.
I completely understand that this man is NOT a writer first and foremost. He didn't have a ghost writer on this, and that is more than admirable. He's an astronaut who's done some of the very coolest stuff anyone's ever done in their lives, and it's perfectly okay for him to both trumpet his successes and give us some pointers in how that success occurred. Heck, his educational initiatives alone are phenomenal (and CSA should give him the hugest retirement package for that). But that doesn't mean that I wished the book was much more about the cool stuff that happens in space than about the tedious slog that is an astronaut's life on Earth and even in space.
It is, in the end, eye-opening though and I'm glad I read it, if only to understand both the thrills and the banalities of space travel.