The best book in the series so far, with a culminating moment that is fantastically rewarding. Although I love this series, I struggled to recommend it to others due to its length. But after this book I can't not recommend it. The end of book 4 makes the wait well worth it.
The slow unrushed unravelling of the narrative is delicious and well constructed, without a sense of dragging; I never felt frustrated with a scene. If you are in a hurry and feel pressured to read a lot of books, this may not be for you. You can and should expect to take your time with this one.
The focus on mental health and the reality of trauma is one of the great strengths of the book. I really cannot say enough on it. It drags the genre of fantasy (perhaps with some readers kicking and screaming, based on other reviews) into a modern sense of humanity.
Finally, the fact that in over 4 massive volumes Sanderson has not needed to lean on the crutch of pornographic story telling like so many other modern fantasy writers is truly marvelous and refreshing.