I went with the Plat Earth and Jail Guards. Both for different reasons. Plat Earth due to the variety of ways of change and the guards due to the totality of the takeover (and the hot uniforms).
Close three-way tie behind these are the Zombabes, Headlights Hotties, and Sentius's Robounits/Controlunits. Would have been a four-way if the Club Pump girls were included.