I listen to a lot of audiobooks, read a lot of library books and e-books, still somehow never have enough room on my bookshelves.
I have found Scott Kelly a lot more engaging in interviews than he was in this book, which could get a little plodding at times, but I still enjoyed it for the most part. It's certainly the most detailed and emotionally-open description of the long-duration missions on the International Space Station. (Alternating chapters were about his childhood, military career, and other NASA missions both as a space shuttle pilot and on the ISS.)
Unlike Mike Massimino, I would never describe Kelly as the happiest man in space. Even though he talked a lot about what he liked about his work and why, a lot of the book focused on the difficulty, deprivation, and tedium that comes with spending months and months away from life on earth, often with just two other people. NASA deliberately ran that man through the wringer to see what happened, and it doesn't seem to have been an entirely enjoyable experience, either physically or psychologically. The crap this man willingly put himself through through to further the science behind space exploration is flat out heroic.
I'm making it sound like this book was a drag, and it wasn't entirely. It was on a certain level good to read a book that wasn't 100% WOW SPACE! Kelly was more willing to criticise NASA and Roscosmos when he felt like they're letting the astronauts and cosmonauts down, which was a nice change, and felt more honest. He did seem to have liked his work, (most of) his co-workers, and being in space on a general level (when the toilet and the CO2 scrubbers were both working). He also seemed to be naturally a little more of an Eeyore than either Hadfield or Massimino, I think part of that being his military background, and part of it being a general outlook on life.
I would totally recommend this if you're looking for what's going on with the space program in the past few years, but if you're looking for something more fun, and frankly better written, I'd point to Massimino or Hadfield.