The issue with Gundam Unicorn is that it sort of sits at a paradox. As a standalone, it's a hell of an anime; but your experience greatly depends on whether you have the knowledge of the Universal Century (you know, Mobile Suit Gundam) to fully grasp the scope of the anime. Unicorn serves as the penultimate conclusion to the Universal Century story that started back in 1979 in the timeless tale known as Mobile Suit Gundam 0079, the OYW (one year war).
Growing up with Gundam, the story seen with my eyes absolutely differs from those who wanted to simply watch "a mecha" or "a gundam". Go find a Gainax anime or Studio Bones anime, for Mobile Suit Gundam Unicorn is a direct continuation of CCA (Char's Counter Attack) rather than a new high budget Gundam project. It's not simply a Gundam... it's THE GUNDAM, and the final chapter for that matter.
An example, those who rate this lowly also believe Banagher Links is a whiny two-dimensional cookie-cutter protag, and that Riddhie is an emo cry baby, and Mineva Zabi is a lifeless zombie, and Full Frontal's a bad guy who has evil/bad intentions and everyone should die. Those are associations created by those who do not fully comprehend the story told.
If you haven't watch the previous TV series, and many times before for that matter, you're better off not watching it at all because it's not meant for you. This is an entirely exclusive experience, and you're not welcome to watch or rate unless your a fan of Mobile Suit Gundam... because Unicorn is simply not meant for you. If one plans to watch this improperly, you'll be taking back about a tenth of the experience (that being animation and ost), while Gundam aficionados are getting the full 100%.
On a brighter note, it's never too late to watch the classics, because you're missing out on the most important anime of a lifetime. Go back an enjoy the masterpieces that are MSG 0079, Zeta, ZZ, CCA, even the OVA's 08th MS, and 0080. Go ahead and enjoy the metaseries and immerse yourself in it's rich universe. I may have came off as pretentious or discouraging, but truth be told, it is what it is.
On a side note, don't you dare read this and think you're ready
http://kotaku.com/5987499/heres-what-youll-want-to-know-before-watching-gundam-unicorn
Oh yeah, and Art/Sound/Characters/ Enjoyment/Overall 10/10, like that matters.
