I really enjoyed the beginning but I disliked the more linear endpoints. The kingdom rules were a little wacky and did little more than facilitate the advancement along the (linear) plotline. If looking for something less .. for lack of a better word.. fast then it doesn't work as well.
Over all, very enjoyable. I just wish the mentality of the beginning APs were carried through to the end but I can also understand why that isn't very feasible.
Oh, to any DMs running this AP, I recommend reading as much of 5 and 6 as possible as early as possible and figuring out how you want them to play into the early APs - it is a very different tonal shift especially for book 6. The best games I've seen, read, or run have added elements of the finale tied into the earlier books to give it a feeling of being large instead of just finishing large. It is as if watching star wars and after 6 movies they reveal the emperor instead of during the second one. Just seems odd, at least elude to him!