Guy Haley has been highly praised by many book reviewers. For example, Alex Hormann reviews Haley’s crime sci-fi novel, Flesh and Steel. According to Hormann, Haley does a fantastic job at building a very gritty and dark setting that is believable. The plot is brilliant, as it shows a rather unexplored area of a larger setting. “In a universe as large as the forty-first millennium, having multiple stories in the same location is a nice change of pace. Varangantua shows the civilian side of life in the grim, dark future. While it still feels like a part of the larger setting, it’s distinctly its own thing.” Hormann also talks highly about the characters Haley creates. “Having one of the main characters be a tech-priest is a useful window into the world, but though we get a look at their inner workings, there is still an air of mystique about them.” He also writes, “We also get few chapters from the perspective of Lux. Not-quite-human viewpoints can be tough to pull off, but again Haley does it with ease.” Hormann talks highly about many writing elements Haley utilizes and recommends the book. 

Another book reviewer by the name of Coda, working for Goonhammer, highly recommends Haley’s novel, Dawn of Fire: Avenging Son. Coda starts off by saying the review of this book is tricky, as it is the start to a planned series that will likely last for a long while. The book, and Haley, has a great amount of pressure to kick off a series which will be vital to Black Library. Yet Haley manages to pull it off and write an excellent novel that can be built off of in many ways. Firstly, according to Coda, the novel struggles to start off in an era which has been covered numerous times by other authors. Coda says it feels rather slow and uneventful in the setup of the novel. Yet Haley’s novel drastically improves in the last two-thirds of the book, getting to the real meaty part of the story. Coda states, “Once it does start moving, Avenging Son draws you in and demands your attention.” and also, “At the start of Avenging Son I was wondering why the book existed and by the end I couldn’t put it down.” He also highly praises Haley’s characters, saying they made the book a fantastic piece of work, “Nison’s [a character in the novel] chapters elevate the book from being merely ‘good’ to ‘excellent’...” Overall, Coda gives it a thumbs up and recommends readers to read, “Avenging Son is a very good book. The first third is a bit of a struggle but once it finds its rhythm, it’s a fantastic work that’s a must-buy and sets the stage well for the Black Library’s new foray into a large fiction series set in the 40k universe.”