The good:
This anime is a nice extra to watch after you've finished both of the stories of the game but still want something more out of this series. It adds extra scenes that lack from the game and generally expands on scenes that it did have.
The bad:
As a standalone anime it isn't the best. If you haven't played the game, you probably shouldn't bother watching this. While in The Good I said that it adds scenes that the game lacked, the game generally does the story much more justice and doesn't leave you as confused as this anime does. Animation and art are okay but nothing to brag about and the story feels like it's rushing forward far too quickly, and at times scene composition feels very off.
Conclusion:
Play the game first, watch the anime after. In no way is it necessary as the story is the same, but as said, the anime does add something new to it as well. Plus you get secret codes from the anime to use in the game.
