This book truly convinced me that Pretty Little Liars is far superior to The Lying Game. Sorry, Sara. I was originally rooting for The Lying Game, being as it was the underdog, but Pretty Little Liars just towers over its opponent.
Shepard does the quadro-narration thing very well. It seems like a difficult thing to do, but she pulls it off, and she does it well. I don't ever confuse the girls with one another, which often happens in books with multiple narrators. (I heard that Dearly, Departed is narrated by five different people, which I'm sure is a colossal fail.)
The struggles the girls face are quasi-unrealistic, but Shepard write them like they could happen to anyone. The girls are going through much more difficult things than they were at the beginning of the series. Shepard keeps upping the stakes, and I'm not disappointed.
I can't wait for the last book in the Pretty Little Liars series!