I actually didn't dislike the ending until I saw it a second time. The fact that Raki didn't die was a real downer as well.
The first time I saw it I was all riled up. I thought the show was awesome. The first 17 or so episodes are awesome. I just dislike the constant powering up. Especially if, in the end, that's all there's to it. It's like watching an animated gif of Goku going SSJ4 for half an hour. Of course the manga goes further. People said the anime was identical to the manga until the last few episodes, but that's not true. A couple of very interesting parts were cut out. Parts that explained much more about the Claymores and their organization. I'm betting they cut them out because they are directly linked to the rest of the manga and it's story. Which leaRAB me to believe more firmly that there never will be a sequel to the anime. Plus the ending of that story arc is very very different in the manga.
I would read the manga if only the people didn't look like puppets. The art is not on par with the anime somehow.