I really liked the first half. It introduces a very gritty sci-fi world. Very realistic, limited, inconvenient. A fantastic place, but not one where you would want to live. Humanity has colonized the Solar System, but not beyond. A lot of people live in the asteroid belt and that's where the story is set. There is no artificial gravity, no wormholes, no faster-than-light travel, no aliens, no robots.

A lot of good comes from this non-magical sci-fi. For example the heavy acceleration of space ships is something you cannot ignore here. Corey manages to turn surprisingly many of the inconveniences that most sci-fi would rather forget about into interesting plot elements. Space stations spin to provide a semblance of gravity, so "down" is toward space, "up" is toward the center of the station. Lots of nice technical details to contemplate!

The story has two main characters and the chapters alternate between their viewpoints. It doesn't sound very exciting or original like that, but in practice it's done very well. In the first half, every chapter ends with a cliffhanger, I could barely put the book down.

So what was it I did not like about the second half? I think the third quarter or so was too much about the feelings of the characters, who are not very interesting emotionally. I didn't entirely buy the drama. Also there is action but it felt like a side-quest that I wished we could have skipped. So basically pacing issues. The first half is a rush. Main characters (or so you would think) die left and right. Everything is a mystery. The heroes are random people that just happen to get involved. The second half is not like that.

From reading the synopsis of the numerous novels that follow in the series, I'm afraid it's more like the second half. Our heroes become professional heroes, and nothing interesting can happen in the solar system (maybe the universe?) without their presence.

All said, I enjoyed the book and would recommend it to anyone. But it's fine to stop reading if you start getting bored. The gritty technical details, like heavy acceleration effects, also wear out their welcome and I started to understand why most sci-fi opts to get rid of them with magic.