DJI props last a long, long time. I'm yet to retire a prop from wear, even after months of abuse. But I broke a couple or so during some rough takeoffs and landings, just happens. They're pretty sturdy and will last if they don't touch anything while spinning. I wouldn't worry about wearing them out even by leaving them on. I have only DJI props, but tried all kinds (composite hub, metal hub, nylon hub and carbon reinforced one with nylon hub too). They all work and last about the same in my experience, though I really fancy the carbon-reinforced type and the metal hub ones. And I never saw one come off from any P3, ever.