This book is brought to you by the words "sprawling" and "gritty". It very much feels like an early book, with the author cramming in as many ideas as possible, so that the full 860 pages are all packed in. I see bits of The City and the City and Embassytown in here, although they are more polished, paced and balanced books. (Oh, and there's clear evidence here that the author owns a thesaurus, which is tankfully less prevalent in the later books.)
It's fully of jarring ideas, with a pile of intermingling sub-plots. It seems like too many things are happening to the same people, and suspension of disbelief starts to fracture, but then it's addressed within the story. The world is alien but familiar, and thought-provoking. Magic is more-or-less handled as a science, and initially you get the impression that the world is more backwards than ours, but it isn't really, except for huge inequality and an authoritarian government. (The lack of change in what is effectively a high-tech society is somewhat overlooked.)
Not only is the city of the story unforgiving, but so is the story itself. Characters you care about don't get easy victories, and everything remains a struggle. It can be hard work in places, although not unncessarily gruesome.
It fits together well. 860 pages is a serious investment for me (an awful lot of commute time!), but worth it. Definitely recommended.