Alright, first let me say that, the manga is infinitely better than the anime. INFINITELY. But, with that being said, I believe the manga should have ended at chapter 58/59. After that, it's just a crapload of "yeah-right" and "ooookay" and "bullshit". Seriously, I hated the second half of the story. However, the first half was so ridiculously good, that I just couldn't give the manga a bad score.

With that being said, on to the details.

Story
Brilliant. I can't think of anything else that has even come close to something like this. Entertaining, smart, and keeps you on the edge of your seat. You'll want to read the chapter after chapter to find out what happens next.

Art
Looks good to me. Figures are drawn well and the females were good looking.

Character
By far, the best part of this show. The characters were...alive. You felt like you really "knew" the people. Almost like reading a book there was so much detail. There aren't any that follow a typical "stupid" or "cliche" trademark either. Thank god.

Enjoyment
Well, as I said, I didn't enjoy the second half of the story. After the first half, my enjoyment level plummeted. Read the second half, if only just to say you have.

Overall
Do yourself a favor and stop after chapter 57-59. You'll enjoy the manga a lot more and probably be happy with a well thought out ending (as opposed to the chapter 108 thrown together ending).