My biggest problem is that the camera commonly has "false starts" where the video starts recording and suddenly stops again after about a second. I missed out on recording quite a few awesome moments because of this issue. To help avoid this, turn on the voice notifications and listen carefully for the camera to say "video start" or "video stop."
Battery life of the included batteries is about 90 minutes when filming on 1080p 30fps. Battery life is much shorter, about 45 minutes, when filming in very cold weather.
Video quality is okay but not great. The Wide Dynamic Range setting (WDR) does not work as well as other action cameras. On a sunny day, the camera does weird things on the horizon. The horizon sometimes looks obviously digital and the boundary of earth and sky becomes discolored.
The audio quality is not great, the gain is very low (naked camera, not inside the waterproof case)