I saw a guy in the park putting his props on with the provided wrench, and he was really cranking them down, I mentioned to him that it wasn't necessary to use brute force on the props and that it would damage them. Hand snug (not tight) is plenty of force, holding the motor with the other hand. I am waiting for him to lose a prop in flight due to stripping the hub. On the other had telling everyone not to remove the props and to never use prop guards borders on paranoia.