I initially wanted to rate this one a 4/5, but...
It was the first thing I thought about this morning when I woke up. It's rare that a book sticks with me so strongly for more than a few hours, so that's high praise in and of itself.
In addition to that, this book made me cry twice. Twice! That is even rarer than the mental "catch".
For all that, and for a wonderful ending to a series that struck just the right note between mournful and lighthearted, and for a skilled remembrance of all the characters Morris has introduced in the last nine books...this was an ending fitting of the series.
As another reviewer said, though, I don't think I could read it again...at least not anytime soon.