With the help of Myung Chun they created a video demonstrating the different models and discovering some of the pros and cons of the different units. Strobist.com brought attention to a video from johnricard.com showing the difference between the professional ring flash units and some of these newer more affordable units. Check each ring flash's site for specifics like whether you will need additional cords. The Ray Flash seems to be self-sufficient and should fit most standard speed lights, the Orbis requires an off-camera cord for use off of the hotshoe but should fit over most standard speedlights. The Zeus Ring Master will need a power pack. For someone just trying out the ring flash look the Ray Flash or Orbis may be the perfect match. One thing to realize when using a ring flash designed to fit over a speedlight is the recycle time for the speedlight. Recycle time can become a major issue if you plan on shooting a lot with the ring flash.