It's sad to say this OVA is underrated. I believe for the most part it's due to the animation, or lack thereof. I see this as being more like a visual novel than an animation. I think many will feel reluctant to watch anime with such an alternative art style, but despite the lack of animation and most of this being a collection of stills, I found the art beautiful, and the soundtrack is entrancing.
The character development isn't brilliant, but you can't expect a lot within half an hour. This is a very enchanting tale that I'm sure I'll always remember. If you can appreciate the art which stands on its own merits, I'm sure you'll enjoy this.