The storylines were consistently interesting throughout, with the exception of a few slice-of-life/romance episodes, and seamlessly blended realism and fantasy elements in a satisfactory manner (as opposed to being "slice-of-life THEN fantasy", they were intertwined). The show did a great job of showing just how unfamiliar the whole situation was to it's protagonists (especially in regards to Yuji and Kazumi), and conveyed their shock at the truth about the world and themselves very well.
The fight scenes were consistently exciting, and the emotional moments usually hit their mark. Humor didn't really, though there were some moments. The animation and direction were great throughout the show, the art-style and character designs were great and cute, and the soundtrack (provided by Kow Otani) was excellent.
Of course, it had some flaws. There was some unfortunate moments of fanservice that I could do without, and I could definitely do without the creepy insectuous couple of Sorath and Tiriel. The love triangle between Yuji, Shana, and Kazumi was boring and unnecessary. And while the first eight episodes and last seven were all good-great, the middle nine episodes were much patchier, with a few dull slice-of-life and romance-themed episodes and a flashback arc that was okay but definitely didn't need to last 3 episodes.
However, those flaws were small issues, and the show was great as a whole. i'd definitely recommend it to anyone who likes "urban fantasy" (namely, fantasy with a realistic, modern setting).
