Rhino for Mac was announced a few weeks ago. Plug-ins aren't there yet, but you can achieve professional renders using Maxwell Studio (included in Maxwell Render suite*).     

Learn here how to export various file formats from Rhino for Mac, import them into Studio, set up materials, cameras, and such, and then render in Maxwell Render.    

*Maxwell Render Suite includes Maxwell Studio and the Rhino 5 Windows plug-in.