I really like this episode, not only because it continue the story of M'benga, but also because it has this tradition complexity about Kilingon, and lot of action and drama in every character.
I don’t like zombie movies. I watch Star Trek because I like Star Trek, not zombie movies. For an episode to score the highest reviews, it needs to appeal to a wide range of fans, so I would not expect a take on a different genre to score as well as a traditional Star Trek episode.