Yes, it's good, despite being too dark, too depressed, with a bitter bittersweet ending.
But seriously, even if I prefer happy endings, the series was very well made (at least on first watch), and the ending, while bittersweet, was well executed and justified. It's one of those little gems like HanTsuki and Shinigami no Ballad that only few of us have watched because they weren't well advertised and talked about on the forum.
It's those series that makes you have faith that even 6 eps may deliver something worthy of remembrance.