I just went to the store and the OceanSignal RescueME MOB1 DSC/AIS is clearly the best choice right now. The OceanSignal RescueME MOB1 DSC/AIS has DSC, but Kannad unit doesn't have DSC signaling and it's about twice the width. They're approximately the same length and depth. The OceanSignal RescueME MOB1 DSC/AIS is about the same size as a Maglite 2-Cell AA Mini Flashlight.