3.5 stars, really. I liked it halfway between Looking for Alaska (3 stars) and An Abundance of Katherines (4 stars). 
 But what I REALLY like, better than any one of these books individually, is the Collected Work (and Preoccupations) of John Green. I think these books are theme and variations. A working and reworking, a commentary upon each other. And I think that THAT is something interesting to watch unfolding. 
 Take, for example, Green's much-touted fascination with the Manic Pixie Dream Girl. Alaska was one; I'd debate Lindsey (I think the Katherines actually fit that characterization better). In this book, however, he utterly deconstructs the MPDG. Unpacks it. Recognizes the damage it can do, the harm in shoehorning a human being into a trope. 
 Knowing me, I have more to say, but it is late and I am tired. That's all you get for now.