Highschool of the Dead. When I first heard the name, I though it was a parody. I don't really have a good reason for it. Of course, I heard about it when anime came out, so anime being slow every week and all that I decided to read manga, and I literally couldn't stop.
What you should first know about manga, if you've seen the anime, is that it has much less fanservice than anime. And that's why it's better. There is still ecchi stuff around, of course, but there are no silly scenes of completelly random panties whenever the wind blows.
So, what is HotD about? It's about kinds running away from school, love, hate, weird teachers who make their students have orgies in the bus... and above all that, there are "them". Zombies. Typical, one bite and you're a zombie. You're done with your life - you became a living dead.
If I read something like this, I'd never read manga or watch anime. But there is something else in HotD. There's amazing mood, great dialogues, which keep you reading. When you read a chapter and look back to what you read, you will find out that you can put the whole thing you've read in two sentences. Yet, while you read, it seems like there is always something going on, something which keeps you wanting to read more. This is one more thing in which manga kills anime. It's only my opinion, but in anime there is way too much fanservice and you can't really concetrate on the story, and even though anime should have more tense with music and all, it seems much more relaxed. Some scenes which are really awesome in manga, which I'm imagining slow, with some sad music in background, in anime they're just skipped through like they are not anything important.
What you should have in mind is that this is NOT masterpiece. It's FAAAAR from masterpiece. Why? Firslty, masterpiece anime needs to have touching story - HotD doesn't have it, but it doesn't really need it. It's not supposed to be anime like that. It's like saying a comedy sucks because there are no tragic moments in it. Second, when reading/watching masterpiece you're supposed to feel happy, sad or whatever the story is like at that moment. You're not reading HotD because you're feeling sorry or happy for characters, you're reading it because, as I said, it kind of has atmosphere around it which just makes you read more and more. There are some heart braking scenes, but that's just not it, the scene soons changegs into ecchi or zombie attack, so it's over even if it had potention to be good.
So, I will repeat myself, don't jump into the manga expecting a masterpiece and hellova good story. It's not. The story is, in lack of a batter term, amazing.
If you look a bit deeper, you will see that it's not a story about random kinds escaping from zombies and just fighting them and going from house to house trying to save their heads. It's about people dealing with themself, trying to overcome their own fears, thinking about their precious family and friends, are they alive or not. There are no longer ranks between people, wether you're homeless or a president, it's all the same now. Nowthere are people who can survive and those who can't.
I'm having really hard time rating series because of this. It's like exactly between nine and ten in my personal, biased, opinion. Trying to be not biased at all, I would give HotD an 8 maybe, so I decided to give it overall 8 - all other ratings are biased:
Story - 9
Art - 10
Character - 9
Enjoyment - 10
Overall - 9.5 (biased) and 8 objectionally.
I highly recommand giving these series a try, wether you've watched anime or not - it's worth it.
