Storyboards are one of the most effective methods to pre-visualize a story: a sequence of illustrations or pictures portraying settings, characters, actions, and events. This graphical representation is a sort of roadmap that guides users throughout the story. The storyboarding process is a key step for both movie and videogame productions, allowing creators to visualize the scenes and find potential problems before they occur. Whereas storyboards are usually drawn or sketched in 2D, recent technological advances allow storytellers to cope with 3D characters and scenes. A 3D approach overcomes 2D methodologies as the storytellers can achieve a better understanding of spaces, objects, lights, and camera movements. Moreover, extended reality (XR) technologies can enhance these benefits by adding a feeling of immersion otherwise not achievable. This manuscript investigates and compares two XR-based storyboarding solutions, which share a common graphical user interface. The proposed system has been tested involving both domain experts and students in a tabletop scale scenario. Experimental results clearly indicate that the virtual reality-based solution outperforms the augmented reality one from the usability point of view; moreover, a lower workload is experienced when an input interface based on physical controllers is available.