Setting flags with a laser is by far the fastest, easiest, and most accurate way of setting flags. One person can do it without any communication problems. Now with regards to the safety issue, looking at any bright light will usually result in some sort of vision imparement. Most of the time it is short term. Flash bulbs, halogen, and the sun are examples. With a laser though, the light is intense and concentrated and therefore one needs to be more prudent with them. In other words don't sit there and stare at one. Up close these might cause permanent damage. Most in use diffuse the beam with distance and thus reduce the concentration as you get farther from the source. One could remote control the on/off or have an bench assistant switch it as needed when anyone is about to cross into your path. A caution sign at the bench might be helpful to the uninformed. A little care on both parties will elimate the safety issue and we could still have a great tool to use.