I so wanted to love this. It was nominated for a Philip K. Dick Award and I like the writer and her style a lot, but there were three flaws that kept me from enjoying it. One, pacing. The first half of the book is boot camp and it's pretty cliche and dragged out. It's nothing we haven't seen in Full Metal Jacket, etc. It even includes Clancy-esque expositional sequences like six pages describing 13 different kinds of bullets in detail. Yes, the author is clever to have thought of it in detail and researched ammo enough to make it convincing, but we only need to know it when the ammo is used. Many of the kinds never come into the story, plus, by the time the ones that are do show up, it's far enough past we won't remember most of these descriptions. This is one example of a few such expositional drains that just slow down the pace, make you want to skip pages, and delay the story.
But these two are minor compared to the bigger issue: the protagonist is incapable of failure. She is never in jeapordy because Johnson gifts her with the gifts she needs to conquer any obstacle. Whenever a problem arises, Johnson just gifts Ia with a psi ability or precog revelation that gives her a solution. So there's never really any doubt about the outcome. She can read the future and thus predict it and be prepared for anything. It makes is hard to maintain suspense when you know she won't die and that she'll win. For me, that just ruined the story. And she's basically invulnerable, so she never meets her match.
It's unfortunate, because Johnson's writing is strong and her character building is not just well done but her characters are interesting. So is the delimma/premise and the world. It's future Earth, basically, with marines out amongst the stars. And while the action packed second have is much better paced and keeps you turning pages, the character flaw issue becomes more bothersome here and really gets in the way. At least it did for me. There are good supporting characters, Ia herself is interesting but her lack of vulnerability derailed it for me.
Good for military scifi fans and part of an expected 4 book series with duology follow up.