I've been flying my P3 4k for about 18 months and an Inspire 1 V2 for 5 months now. After every day of flying I would download the video and still to a 4TB drive. Then reuse the SD card the next flight. A couple of days ago I went to edit video and what a surprise, not a good one. The 4TB Seagate was dead. Too many bad sectors! I used every method online and took it to the local guru. Nothing worked. I've lost 18 months of video and stills. From now on I'll keep separate SD cards for every project to protect the original footage and backup to a SSD. How many backups do you use normally??