I really like Book 1 ... well the first half of book 1, it's always so nice to read that after one of the darker ones to remember the innocence of it all at the beginning. But the story line itself I could do without ... so unfortunately Book 1 appears near the end of my list.
Three and five are pretty much tied. As much as I like the earlier ones, the later ones get much darker and more interesting. The ending of the first one seems a bit trite to me. You killed him with love. . .blah.