R.E.I., internet.
That was 7 years ago. I used it last month, for the first time.
I was at Stokes State Forest in N.W. New Jersey. It is not a place that is easy to get lost but cell signal disappears about a mile into the forest. I bought it because about 10 years ago, I was 3/4 up a ridge and encountered a descending hiker. She had a sprained or broken leg and asked for help getting down from the ridge.
Five years ago, I was in my car in the White Mountains, N.H. A biker went off the road and was injured. Again, no cell service. It was about 40 minutes before a biker could reach town for aid....another hour before assistance could get to her.
So I got a signal beacon, just in case.
Back to last month. I was in Stokes and encountered an elderly man, flat out and down, next to a stream. I called to him, no answer. Also, no cell service. I deployed the beacon. Then I sent my friend back about 2 miles to where there was a cell signal. My beacon doesn't have 2 way communication but there are others that do.
I climbed down to the spring and called to the guy. He woke up and said he was just resting.
From there, I began walking to where my friend was walking. About half way there, my cell phone went off. It was a dispatcher from Pensacola Naval Station who was trying to communicate with me.
I described the emergency and told him the "emergency" was resolved. He thanked me and terminated the call.
The point is, these things do work. Consider getting one, maybe even if you are not in forests. There are parts of the U.S. that are not cell equipped. It may save yours or someone's life.