The option to set a small focus box with the EM5 upgrade is nice to have, but I wanted to be able to switch easily between small and large. Turns out that this is possible. Basically you set up the small focus box as default for all your frequently used presets. Then you set the home focus location as a center point large box. If one of the function buttons (Fn1 in my case) is set to Home (AF focus point reset), then pressing the button toggles between large and small focus boxes. At least that's how it works on my camera. Edit: it seems that for this to work you have to select one of the presets after the camera is switched on. I must confess this somewhat reduces the usefulness of the idea.