I find the usual KyoAni art combined with the more serious action scenes jarring. It is mainly their fault for associating that style with moe crap, but it is also a fact that they can use different art styles more appropriate for this theme (FMPSR, Haruhi). The comedy was great though, even if that is really odd for this type of show. In a sense, this series is a serious venture for the studio, combining their usual comedy direction and delivery to a more serious plot.
I really dislike tennen megane characters, so I am mostly watching this hoping for some better characters to show up.