I watched this movie some months ago, so I'd probably miss some details on this review. I haven't read the manga so I'm no going to compare it with the manga (which as far as I know is better than the movie).
I found the story quite interesting and well executioned. The plot revolves about a virus called "Medusa" which almost instantly petrifies it's victims. A big pharmaceutical company gives the chance to 160 people to survive by freezing their bodies and waking them up several years after. When they wake up they find that everything has been taken over by monsters, and they have to run away from this place if they want to survive. They do a good job developing the plot but, I found that the last 15 minutes of the movie were quite messy and rushed, like if they wanted to finish that quickly.
I liked a lot the animation. It was visually stunning with all the details. Sometimes you can notice the use of CGI, but they didn't bother too much.
The sound, while not spectacular or memorable, fits perfectly with every scene and helps a lot developing an atmosphere of fear and despair, immersing the viewers into the movie.
Also the voice acting was fine, every voice fits with the character.
The only thing I don't really liked of the movie was the character development. While the main character was developed really good, the other ones were hardly developed, making them no more than companions of the main character.
It has a good story, great animation, a fitting soundtrack and an interesting main character which is important for the plot development. It's not the best movie ever made but you'll probably enjoy it. I gave it an 8 instead of a 7 because I enjoyed watching the movie and I felt that giving a 7 could be a bit unfair