This is the ending that book three should have had. The first half, A Storm of Swords: Steel and Snow, just wasn't strong enough to stand on its own. But that's okay as the second half more than makes up for it. From the off, there are bodies. Not just secondary characters either, but people we thought were going to be key players in The Game.
A number of characters get built out a lot more as well. Jamie continues his transition to three-dimensions with the start of a conscience. Stannis starts to come out of his shell a little and Petyr's role in the history so far starts to make a lot more sense – he did warn us not to trust him!
As a combined single book it would have been a five star rating, as part two more than rescues any failings in part one. I strongly suggest reading them back to back, and thinking of them as one logical book, if you're going to buy them individually.