The main character, Clare, is ranked as the "weakest" of the Claymore. This makes the series an "underdog" story in more than one way. The Yoma (demons/monsters they fight in the series) are stronger than the Claymore, but because Claymore are half-human/half-yoma they are able to do battle with the creatures. This story deals heavily with questions about humanity and right and wrong. The main character has a strong background story, and those close to her are heavily influenced by her. The story aside, it is very bloody and violent so it's not for the faint of heart.
This anime didn't sit well with me at first. The panning shots are too fast, and you're not left a lot of time for the emotional connections to develop. This is no fault to the story, this is actually a decent adaption from the manga. However, it really is moving 2.5-3 times faster than the manga series does. They truncate a lot of the dialogue and pan quickly through the emotional scenes. There are plenty of scenes that are done pretty well, but the anime really fluctuates between "fair" and "excellent." This should have been a 40+ episode series if they had done it right. This doesn't kill the anime, but it does cripple it quite a bit. Also, the ending is very different than the part of the manga it's adapted from. They still leave it very open without tying up any of the lose ends because they're still being dealt with in the manga series. In my opinion, it would have been better if they left it exactly the same as the manga series, but it wouldn't have been the happy ending they left it with.
All that being said it's still a good anime. Manga fans should be ok with it (we are used to manga being butchered when going anime), and anime fans should find it worthy of a little praise. I mentioned before that it is a good introduction to the manga series, but if you want to pick up where this left off then you will want to read the overlapping section that the ending changed so you can see what really happened. It's much more dark, and it really is a lot cooler.
Add this to your list if you get around to it, but definitely check out the manga series.
