I was warned about this book being mostly filler and a massive slog. I actually didn't find it to be so!

This book does occupy a weird place, being what was originally intended to be the finale of the series, but now stuck between book 2 and what became book 4. So there is some feeling that the ball doesn't move as much as you feel like it should. However, I enjoyed the whole thing completely and chugged through it at a steady pace. I never got bogged down - I enjoy Roran's arc a lot, and am happy to follow along with Eragon's steady quest to become the most overpowered individual in the realm.