Genocidal organ is probably the weakest of the three ITOH movies. It seems to use two main themes; one is very innovative and possesses extraordinary original potential, while the other is an old worn theme, which has been used many times in the past. The movies starts with the original theme and pushes this very well until the reveal, where its almost casually revealed and thrown away for the old, well-worn theme, which continues until the end of the movie. There is nothing wrong with the conclusion of the movie, but it's been done so many times it can be very hum-drum.
This is very unusual because in the first two movies the original innovative themes are run to the end of the movie, so I am unsure why Satoshi Ito did this in this movie. I suspect because he was trying to follow the primary plot of a computer game so had to go down that path.
Apart from this the animation is excellent, but I found the characters a bit lifeless. This is not a major issue, but does not help during the boring bits and its hard to identify with the characters in any manner. The action scenes are very good and first the first half of the movie the conversations are interesting. Its only when you discover the plot has moved to such an old plot lines that it begins to lose its interest. My suggestion is to watch the other two movies and if you like them, watch this.