I loved the first book of this series, and I actually also really liked the second, but there was one thing kind of bugging me and that was the love triangle. Of course it was expected from the first book, but I was hoping it wouldn't come through. It did, to some extent, but thankfully it wasn't nearly as bad as I'd feared. It was tolerable, at least. Also, in the end, (view spoiler)[ Clara did choose the best friend, the one she was with first and the one she wasn't 'meant to be' with, (hide spoiler)] which I was happy about. 
 Other than that, there were so many more interesting things going on in this trilogy, some of which I saw coming (such as what happened to Clara's mother) and some of which I didn't (such as the Angela storyline and what happened with Clara's dad). I liked the character development of not just Clara, but the other characters as well. It was all quite realistically written, especially each character's feelings about and responses to the situations they were faced with. 
 They went through a lot in this trilogy, but nothing felt over-the-top or too much. There were some surprising twists without things getting too complicated; the book is perfectly balanced between an easy read and a thrilling and exciting one. It never got boring, because the moment it threatened to, something else happened that tossed the characters into yet another different situation they had to solve. The conception of hell in this book is interesting and, actually, quite scary, as are the Dark Wings. 
 As I said before, I wasn't expecting much of this trilogy after having read other angel books I felt were very dramatic and cliche, but it was much better than I thought it would be. I very much enjoyed all three books and I am glad I picked them up after all. A good en exciting YA read.