I prefer to fly with the 720 mounted vertically to maximize the visible map ahead of the plane. My Zenith STOL CH750 has a lot of window area including a top window that serves as the cabin's roof. So, the direct sunlight infiltrating the cabin and panel can at times rival a canopied aircraft!
I know AP sells a sun visor for the 720, but it is shown attached to one mounted horizontally. I wasn't sure if the same visor was a good fit (or even would fit) a vertically mounted 720. I found that the eBay cheapy (<$5 delivered!) generic visors for 4.3" to 5" automobile GPS' fit the 720 as if they were made for it! Of course, it would be better if the shade extended further down the sides of the 720, but it definitely helps - particularly with high sun angles.
John
N750A