Hello everyone,
Here we are for another review, this time of a yuri action anime original series named Simoun that aired in the long past 2006 and got quite some attention from the blogosphere at the time.
Let's start with a synopsis :
In the world of Daikuuriku, everyone is born female, and chooses which sex they wish to become at age 17. In this world, the peaceful theocracy of Simulacrum is guarded by magical flying machines called "Simoun", which can only be piloted by young girls who haven't chosen a sex yet. The Simoun can activate a magical power known as "Ri Maajon" that can destroy large numbers of enemies at once. When the industrialized nation of Argentum decides that it needs to invade Simulacrum to acquire the secret of the Simoun, war breaks out, drawing the Simoun "Sibyllae" (priestesses who fly the Simoun) into a lopsided battle.
The premise is quite good and very original compared to what the common series show us recently, the real problem of this series how they decided to conclude it in the last couple of episodes.
Yes, because the starting point of the series (if you can stand the strong yuri undertones of the series) is pretty much a masterpiece with a nicely paced action and slowly new information about the world is given to you till you start to understand what is going.
I loved how they reasoned the war between the states and each and every detail differencing the three nations (that are resembling our nations in the past).
Also very nice are all the formation the Sibillae use to execute Ri Majons (even if they don't really explain how these formations create that much destructive power)
The problems start in the second half of the series when the story start to make less sense and they start to put a lot of supernatural feel in it, starting from Dominura crazy screams after watching the content of the helical motor, and ending up with the uncertain end of the two heroine of this series. (basically a "wtf, I watched this for 26 episodes and you don't give me a conclusive ending?")
There are some big hint to religious fanatical behaviour (see the girl captured in one of the episodes) in this series, especially in the antagonist armies that is another big link to our world situation.
The characters are many and you'll likely end up completely forgetting about most of them. There are many hateful character in the series starting from Paraietta and continuing with Amuria, Dominura and many others.
There is some kind of growth in the character personality during the series, especially after the time skip when you see them into their own final body.
My favourite characters are by far Aer and Rimone. The first because of the her energy and never tiring will to go ahead and face her own destiny, the second because well she's cute and she's voiced by Mamiko Noto! 
The graphic is very good for time this series aired even thought you'll need some time to adapt to the particular style used for characters and backgrounds. The animation is mostly consistent and make use in some scenes of computer graphics for the aerial battles.
The sound quality is top notch with many big name working on this project like Nana Mizuki in Morinas's role, Mamiko Noto in Rimone's role, Yukana in Dominura's role and many other. Also very nice are both opening and ending song. (Loved the ending "Inori no uta" sung by Savage Genius)
Concluding this series is likely one of the best yuri series of the last years with the only problem related to the very uncertain end. Nevertheless this is highly suggested if you like the action or the yuri genres.
See you soon,
feal87