I'm often wary of prequels for fear of contradictions, knowing certain things have to go a certain way, knowing certain characters must be safe, that sort of thing. Still, I really never get tired of Hadrian and Royce, and despite the many pitfalls that come with prequels, the author managed to give us a fairly new story with the two of them, with new insights into the characters and how they developed into the people they are when they're introduced in the beginning of the Riyria Revelations.
Royce's cynical, extreme curmudgeon perspective is something that I have trouble relating to, but at the same time, I love watching his views get challenged, and seeing him make connections and care about other people despite his cynicism. He's a complicated character, and I love that. I didn't see quite as much new ground where Hadrian was concerned, but he's still his likable self, so people who enjoy him won't be disappointed.
New characters were introduced that I found really compelling, particularly Lady Dulgath and Sherwood Stow. Both characters had a lot of depth that made them feel very human, and had some surprises in their stories.
The only thing I didn't enjoy here was the point of view of one of the villain characters. The character was just so irredeemably vile that I tended to set the book aside to do other activities whenever that person's chapters came up. If you're someone who enjoys villain perspectives, you'll probably like it just fine. It's just not something I personally enjoy. Thankfully, there wasn't too much of that character's perspective for me to read. It was still well worth it.
The story had mystery and surprise, great character development... really, everything I want and expect from this series.