I deployed an epirb once while doing a flight in the USA due to massive storms and tornadoes in all directions, as it happened, I landed in an Indian reservation on a dirt road in the middle of New Mexico and probably about 50 km from the closest person. I turned the beacon on at about 500 feet AGL when I had committed to landing, I turned it off after about 2 minutes after I landed, exited the aircraft and started tying everything down using shrubs and rocks.
The beacon was a personal one (a little GME410 from memory) and registered in my name to my Australian address, within 60 seconds of activation, search and rescue in Canberra were calling my telephone, shortly after that was the American equivalent who had pulled my phone number of an international database. I explained everything was good, they knew my exact location and send out an Indian ranger to spend the night with me if needed. After about one hour the storm had passed, the Ranger had arrived and after another hour of sunlight the track had dried out enough to take off from.
Just saying that the response to these new generation GPS beacons is within seconds, they have you down in location to about 3 m and I'm sure if it was a real emergency where, I didn't land on the track and crashed into something than I am sure help would have been on the way 10 minutes later. Amazing technologies and something that needs to be taken with you every single time you fly. GME even gave me a replacement beacon for the one that I activated if they could use everything in their survival story series.