All my P3P batteries are also still fully functional. I have yet to have any DJI battery need replacing because it was regularly run to below 10%. Every one them are still good for way longer than 50% of a new battery, so I am still getting more flight time out of every battery than you are, by never going below 50%. Clearly, 50% gets you where you want to
go and back. I need almost 50%
just to get to my destination, so 50% isn't even an option! At most, I see a 10% reduction in flight time over a brand new battery. Agreed on "if it ain't broke, don't fix it!"