The worst case scenario is where the props hit someone or the Phantom drops down from the air and hits someone. Although DJI Phantom dropping causes less damage than any of the bigger multicopters. Propguards might help, but they dont remove the chances of getting damage as you can see in this video: https://www.youtube.com/watch?v=ji3Hii_LZOc They aftermarket carbon props seem to do a lot of damage. And cut deep. I've had one encounter with the plastic DJI props hitting my fingers slightly... Nothing too remarkable happened. So I'm thinking that the damage seen in the video was most likely caused by the sharp carbon props. Someone should do some myth busters type of tests with pork meet to see what kind of damage you get with different kind of props. What kind of damage would the plastick props do in the same situation as in the video?