I got to participate in a game that used Meshtastic and GPS where you walk around a large camp and "capture" different regions. It worked great for that and was a lot of fun.

If there ever where a more serious situation where my life depended on one of these meshes, I would be feeling pretty uneasy. They are absolutely not reliable enough to even consider such a thing. I suppose they might be better than nothing.

To say nothing of what is required to set up the devices. I wanted to put a full dev system on a raspberry pi 3 just so it would all be in one place and I could work on it when in a location with no internet - it ran out of memory trying to compile the massive web app that is the default client interface.