Claymore is goodness personified (or objectified? manganized?). At first glance it's not much: straight forward monster hunting, not so complex storyline, and a bit too few main characters (Clare and Raki).
But the longer you read, the more interested you became. The world start opening up, with more characters, more intrigues. The story starts having more layers of meaning. In the same time, our hero and heroines became more colourful and real.
The mangaka is also quite decisive too. YAGI Norihiro is one of the few storyteller who has the guts to kill characters when the story need. he remind me of George RR Martin , author of A Song of Ice and Fire series. I mean, he introduce a heroine, give her a life and past, then killed her in the next volume, just to make his point. He's good!
Before you dismiss this manga as a Shounen stuff, I recommend you try reading it until volume 6. You Will Get Hooked!
The only complaint I got against this series is the Shounen stuff. What it mean is that: the manga touch lightly upon sex stuffs and politics stuff. Come on! A fighting order composed of female only, that's the source of yuri right there. And romance between normal guys and Claymores are difinitely tragic tales. Politics? not enough details, both about the lands and the organization.
EDIT No1:
13 vols come and go, and my complaints are still the same. The additional details are not being supplied enough. In fact, we know quite a bit more about inhuman enemies than the situation of human countries.
Raki has matured quite a bit. He's got to be quite a ladies' man. Alas, the way this manga were being crafted, I doubt he will get all the girls though. It's so not harem-manga.