The movie is okay but it could have been so much more.
The first thing you will think when you're watching, it is that it's very fast paced and short. It's only about 25 minutes long. I think it would have been much better if they built up some suspense and went through the story a little slower. But I must admit that I've always said I liked Yu Yu Hakusho because of the quicker pace and small amount of filler time throughout the show.
If you can get over the quick pace of the movie it's pretty good. The story is enjoyable and the characters held true to their personalities. I heard that they changes a couple of the voice actors but I barely noticed. Plenty of good action, which you'd expect from Hakusho. The animation and sound were good.
Altogether I found it pretty entertaining but a bit disappointing.
To say in short, this little piece was terrible. Hiei said "Good luck." Hiei and Kurama sounded like very grown men with big chests. All the voice actors were horrible. I think I fell asleep in the middle, the story was just that boring. Yeah. So here's my short review. Please don't waste your time. It just makes a mockery.