(Warning: mildly spoiler-y.) This book hit the spot. This was my first time reading it. I wanted something along the lines of The Ocean at the End of the Lane, and this was equal parts that and dystopian sci-fi, but with a pretty saccharine theme and ending. If it had been a little bit darker/more realistic, i would've liked it even more. 
 I liked that it was both a fantasy and a sci-fi; those are often my favorite stories (Star Wars and such). The flying centaurs were a bit silly, but i thought the fuzzy tentacled aliens and their colorless world were awesome. I loved the 3 witch-like characters and the three unusual child heroes. I loved the kids' family; the cool doctor parents and the weird but very loving kids and the cozy farmhouse they shared. It's the kind of family you wish you were part of. I liked the love story, even if it was way too easy. Meg and Calvin just sort of came together like magnets, but i'm a sucker for that sort of thing. 
 This book is a predecessor of all of the other children's fantasy and sci-fi books i've been reading lately, with the exception of the chronicles of Narnia, which feel far more dated. It shares a pretty obvious theme with Harry Potter, interestingly. Except in this book, the hero is a bespectacled teenage girl with the power of love instead of a boy. But i wish the book had been about love without also being about God. It didn't need to be about that, IMO. This certainly doesn't feel like a 50-year-old book--it's no wonder that they're turning it into a movie; the story will fit right in with all the other dystopia tales that are super popular right now (Hunger Games, The Giver, Maze Runner, and Divergent, to name a few). The dystopian planet in this story is probably the most messed-up one i've ever heard of, come to think of it. They kill you if you catch a cold?! That might be even more outrageous than making kids fight to the death. 
 The more of these kids' sci-fi/fantasy books i read, the more value i see in the His Dark Materials series. I still think they're not appropriate for kids, but for someone like me who likes the genre but can handle more complex ideas, they're pretty fascinating. They turn the good vs. evil trope on its head in a way that is bizarre but really interesting. I may have to go through Pullman's books again one day. I just wish they were a little more warm and fuzzy, like A Wrinkle In Time is. I prefer books that are somewhere in the middle, like Ocean at the End of the Lane.