I didn't hate this book, but I definitely didn't like it either. There were parts that were well written, but the majority of the book was very "meh". I struggled to make any connection to the characters or the story and slogged through most of the book.
Here's how I would describe this book. Imagine Harry Potter as a college age spoiled Emo kid twatwaffle who wanders around Hogwarts in NY with his internal monologue telling us how life is pain, and everything is shit, etc. That's Quentin Coldwater, our protagonist. The premise is a stolen mash-up of Harry Potter and the Narnia Chronicles without any depth at all to the worlds - any time the story is called upon to develop the word so that the reader is drawn in, the author abruptly jumps ahead months at a time, leaving you with a collection of disjointed anecdotes about nothing.
I'd recommend skipping this series unless you're really into long, pointless books that rip off other works, and star characters you'll either not care about or totally hate.