I received this book as an ARC, and I found the characters to be interesting and the overall premise to be intriguing. I enjoyed reading the story and found it to be reasonably well-written for a debut novel in terms of action and pacing.
Although I enjoyed the story, I did have a few technical issues with the writing itself. All the characters speak with more or less the same voice; there are very few distinct speech patterns. This makes it harder to differentiate between individuals, especially if there are no he said/she said tags on the ends of dialogue.
There are also some serious homophone issues that I hope will be addressed in the final publication. As Vestro, a kelpie, spends large portions of the story in horse form, it's somewhat important to remember that reigns are not reins, and bridal is not the same as bridle. Nitpicky? Perhaps somewhat, but it really jumped out at me while I was reading, and it threw me out of the story.