Gasaraki is a very unusual show. It doesn't mind being extremely poetic. It doesn't care that a lot of viewers will regard it as excessively high-brow. I think the director must have watched a lot of art films, especially Fellini.
Gasaraki is not a great show. It is not the next Cowboy Bebop. It does have a lot of elements that don't fit together very closely -- the giant robots don't fit well with the supernatural elements or the realistic techno-thriller politics.
Gasaraki evoked a very powerful mood in me. In the end, perhaps it promised more explanations than it delivered, but certainly it delivered more atmosphere and mood than I had imagined to be possible. I didn't care about the plot -- I didn't even care much about the main characters, and I was very frustrated by the fact that the writing seemed pretty weak for some key character relationships -- but there were a few characters who positively inspired me, and there was a genuine sense of depth to this show.