From an objective standpoint, Kampfer is an otrocious anime.
-No character development
-Mikoto Konduo served no purpose. They could have removed her from the anime and it would not have changed anything.
-Nothing makes the characters standout. They are all average and bland.
-No reason is given for why the main characters like the male Natsuru, they just do. Other harem animes (Kampfer should be listed as a harem anime) actually give some sort of reason for the girls to obsess over the main male character like in Rosario + Vampire (Tskune is sincere).
Sound & Animation:
-The sound and animation aren't bad, but then again they aren't good.
-The plot started out somewhat interesting but then it got progressively worse as the plot unfolded. Things kept happening and they didn't make any sense and they were never explained.
-The plot never came to a conclusion (it didn't come to a conclusion in the OVA either)
-The last episode was just a troll
Everything about Kampfer is bad (except the sound and animation).
Opinion: From a subjective standpoint, however, Kampfer is actually very entertaining if you enjoy ecchi, harem, or fan-service. You will find Kampfer either unbearable or enjoyable depending on your tastes.