Let me start by saying that I bought this movie only because I'm a big Gackt fan and a fan of HYDE, too. I have to say, I wasn't dissapointed by them. I was dissapointed by the plot. Or should I say, the lack of a plot.
The movie's main plot was very weak at best and the whole thing lacked any sort of cohesion at all. I would have to describe it as, 'Some guys and an incidental vampire shoot at each other and they all end up dead.'
The whole vampire angle was the only thing that interested me, but it was almost ignored until the last fifteen minutes of the movie. And when it was finally remembered, it was done in a very cliche manner with the ever-dreaded vampire-angst. Perfectly willing to gun people down, we still don't like drinking blood.
So, in closing, I would only reccomend it based on a love of Gackt and/or HYDE. Gackt looked very cute throughout the entire movie and HYDE looked nice most of the time. If you're just looking for a good movie, don't waste your time here.