Although the Metabones IV is the leading adapter for Canon EF lenses to A6000, there are limitations of the Canon lenses that can be used. That is also true of 3rd party lenses that will not work with this adapter where AF functions, and F stops do not operate or register on the A6000. I really enjoy using the A6000 for events where I am a guest, and I want to be discrete; think weddings, birthdays, dinner parties etc. I really like the picture quality (can you say "dynamic range"), and the camera has some quirky menus, and functions take awhile to get used to, but Sony is breaking away from conventional systems and the conversations about the capabilities of their cameras is nothing but a good thing for Sony in particular, and the industry in general. I have the Canon MK IV, but I am still trying out the A6000 with my Canon lenses to test its limitations.