Animation (personal) : 1, 2, 4, 3
Animation (technical) : 2, 1, 4, 3
Originality : 3, 4, 2, 1
I feel that the first episode is where the animators were really into it.
I'm sure many of them are fans of Alien 9 manga. By the second episode,
they figured out how to draw these characters without insane amount of
effort. Then they were rushed through episode 3. Then they felt kind
of obligated to do a good job on the last one. That's how I feel anyway.
Obviously, they stopped in the middle of the story, but they combined some of the elements from the later manga chapters into this episode. Some of the sequences have more impact than manga -- most of the dream sequences -- but I feel that many of the key events were not handled very well compared to the original manga. For example, when Kasumi was attacking Kumi, they brought in too much stuff from the later chapters of manga. It made it too drastic. All in all, I'd say, the animated version is not really meaningful to those who have not and will not read the manga. If they think that the OVA was great even though they didn't read the manga, oh well. They don't know what they're missing.