Brief review: It takes it's time to get started, but overall, it's worth the read. Ok, let me start by saying that I've read a fair share of shounen when I was younger, but as I grew older I started reading more and more seinen. I think this explains my initial shock. This is a shounen manga, and it starts really shounenly. I found it boring at first, while the premisse shows potential, you never feel like it's being explored to it's fullest. The story starts out linear, with a lot of shounen tropes and somewhat boring characters; it's a simple good vs evil story. Butthere is development! The story branches out and more interesting characters are introduced, and the ones that were already there get a proper development.
Overall, the manga changed my mind halfway through, and turned out as a really solid, amusing manga. I'm writing this review because no other informed me about such change, and I kept wondering if it was worth keep reading this manga. And it was, it was an enjoyable experience.