4k video is just great! I researched these GoPro style cameras for a while before purchasing the Remali CapturePro. Bought it for a wedding in Sint Maarten. Nervous after reading some of the reviews from people struggling. For the first dive I set the camera to record at 4k 60fps. The battery lasted for every 40 minutes of diving. The video was great, crystal clear. For the second dive I changed the batteries just in case (there are 3 in the kit). I set my camera to the 20mb image mode and started photographing coral, lobster, etc. Then a big shark appeared in the area and I switched back to 1080p 120fps video mode and the video quality was very close to 4k. There were no problems with files and their editing. Very happy with this purchase!