The Unnaturalists is a different type of steampunk to your usual type. It is set in a different world, where the original London was magically transported to a new world, full of magical creatures like Sphinxes and Manticores. This book has a combination of magic and science, which allows it to extend it's marketing, as the characters try to classify magic through science. This is a combination that I have never really seen before, especially with these types of creatures.
The main characters in The Unnaturalists are Vespa and Syrus, with the book being told in Vespa's POV, but with alternating chapters to show what us what Syrus was doing in 3rd person. I think that this was confusing, as it was hard to tell the different between them, especially when they were doing things together. I reckon that it should of both been in 1st person or 3rd person, not two different POV.
It was also strange as Syrus was younger than Vespa, and his part of the story was told in 3rd person, basically trying to hint that Syrus isn't that important, but he is just as important. It is also very hard to sympathize with Syrus, as I just wasn't able to connect with him. Even though many tragedies befell him, I just couldn't feel the grief I was meant to. And the tragedies also gave the impression that Vespa is a stuck up snob, and not a very likeable person, she is also that that bright.
The Unnaturalists is a good steampunk to read, and has a fantastic world built inside it's pages. It is worth reading if you enjoy these types of books.