I loved this anime. I thought the animation was beautiful and it had an interesting storyline and very endearing characters. I love the world ABe Yoshitoshi made for them. I would recommend it, but only to a limited audience, who I knew could appreciate it for what it was. I would not say it was a masterpiece, as I felt it was far to short and could have been further developed.
Also, for some the amount of things not explained would be a pretty big problem - however, that could have been forgivable had the makers continued to introduce us to more of this world and explored more of the relationships. Because these things are sort of left on the shelf as the plot goes on, I only would give it an 8 or 9 (my decision fluctuates directly after I've seen it again) out of ten - however, it definitely had 10 potential as far as good anime has gone.