I'll agree they are a valuable tool for getting someone's attention.  Last month LL came and helped my move 8R wide planter down a narrow, curvey but busy country 2 lane.  He had a 'flashey, blinkey light' on top of his pickup, to my amazement, people actually slowed down and pulled over or stopped so we could safely pass.  Neighbor said the same thing when they started putting them on new equipment.