Also vibrations severely affect bearing life. It didn’t take much of a chunk missing for the prop to run out of balance. Any damage, change the prop, cheap insurance.balancing the folding prop is a bit tricky. usually folding props can let to tighten the screw that holds a half of the propeller in the assembly hub. google a 'how do you balance a folding prop' topic. usually a well balanced prop lasts as long as it takes to smack the model into a tree or asphalt, or anything hard enough to damage the prop and a result of that is very visible, usually. do not fly with a damaged prop, ever - as it increases vibrations above the threshold that keeps model stable and then different firmware may act differently. just to replace it every 10hrs if prop is perfectly fine is not needed. to pre-balance all props to make sure you not introducing unnecessary vibrations is a smart thing to do.