Curlardoch makes a good point
In the absence of mobile phone signal and you are walking alone and if you were injured how would you get a message out that you were injured? Here's my story
I walked the Scottish National Trail alone in 2018. I knew for the latter stages (ie Cape Wrath trail) signal would be intermittent to non existent. My wife insisted I find a device that could send a signal to her to let I know i was safe wherever i was so I purchased a Garmin In Reach:
https://hikingguy.com/hiking-gear/in-depth-garmin-inreach-explorer-review/This allowed me to send a pre defined message which you can set up before you leave at no cost. The recipient receives the message together with a link which shows where you on a map together with the Lat\Long coordinates. the device can also send track points to the recipient etc. I do not use it for navigation
Coming off the Falls of Glomach I was hit by a very severe storm. I made it to Maol Bhuidhe Bothy. Sent my wife a signal to say I was ok. Leaving Maol Bhuidhe Bothy the following day I was hit again with a severe storm and fell into the River Ling (which was in spate) I completely submerged. I got out and eventually after 3 hours + finally made it to Bendronaig Lodge. I then sent a another message to my wife. She received the message but thought I was in trouble. as it looked as though I had not moved far (which I had'nt) my mistake was not to have sent her a free text email message from the device. My wife concerned rang Police Scotland and they coordinated with MRT to locate me via the co-ordinates on the predefined message which my wife was able to read out to MRT and Police Scotland. Later that evening the Head Stalker from Attadale (Tom W) came into the lodge and asked for me by name as there was another walker sheltering from the storm. Police Scotland etc were absolutely brilliant. Tom indicated that the storm was the worst he had ever known
I take out a contract to send messages etc which is about £30 I think for the Inreach but i can suspend the contract once i have finished the walk. i will be taking the device again on SNT this year. while trying to raise money for Childens Hospices Across Scotland and yes I will be walking alone
I have also purchased a PLB review here registration simple.
https://hikingguy.com/hiking-gear/acr-resqlink-view-plb-review-acr-plb-or-garmin-inreach/Response times for both devices is per standard there is no lag to my knowledge in alerting rescue services
Expensive'? My family want me to return home.
I often see You Tube videos with the super light gear etc being displayed but rarely do I see a torch or whistle or PLB amongst the kit
Stay safe out there
ps : I am an experienced walker. I did send Tom a very large bottle of whisky