I happened to dig this out of my backlog and watched it this weekend (followed by reading from Chapter 32 to the final chapter 84). This shit was good.

I've read that the biggest complaint about the anime part is that the pacing was slow, but that's only as true as speaking slowly enough to make your point heard. It wasn't unnecessarily slow.

The manga's pretty much a must read if you liked the anime since the latter gives no closure whatsoever.