If you were anything like me post-Sleeping Giants and felt like "eh, that was alright. Like, it was a decent enough story, though nothing was quite gripping enough to throw me along, mostly it was written in a format that was easy to digest and didn't ask too much of me." If you ended it not knowing if you'd pick up the second, I would actually recommend picking up this sequel.
I had no real objections to Sleeping Giants, really. But it felt a little rough and even by the end of the story I didn't feel any real investment in the characters. There was too much a level of detachment; even when Rose died all I could mentally muster was a shrug.
I don't know why there was so much more attachment I felt to the characters in this book. Perhaps Rose's inner conflicts in this book just made her more interesting. I like that the author acknowledges how different people can be in the space of 4 years; Rose is essentially an entirely new character in this book and though I'm half-tempted to be a little "she's totally unrecognizable", there's a part of me that really liked that she was very different. Whatever confidence and impulse she gained in those 4 years was gone. It was like if my teenager self suddenly popped into my current life, post the trials and tribulations of the past couple of years. Whatever the case, I found Rose to be a much more evocative character in the book, even as her role evolves wildly and changes, or perhaps because of it.
Kara and Vincent's conflicts were interesting, but their plot didn't quite get me the way that Rose's did. Perhaps it's because, like many authors, the kids are written with dialogue not that different from adults. The only real indication that they're a kid is the physical description and just the information that they are one. They certainly aren't a kid in personality, even considering the amount of trauma that they go through.