GPS is a big part of what we do here at Trail Genius, so it goes without saying that we have a lot of different GPS devises. Some of the cameras we use have GPS built into them, but for long events their shorter battery life can be limiting, plus the time it takes for the camera GPS to sync when you change a battery is frustrating. In the end we typically use a second external GPS as a backup to the camera, or run a non-gps camera with and external GPS so we get maximum battery life.