When SPOT released their emergency messenger years ago, I made my first experiences with such a GPS messenger, the SPOT of the first generation. Purchased for a trans-Asia trip in which at that time was a bit more adventurous than it is today you can imagine. That SPOT Gen1 device was already very robust, easy to use and only slightly larger than a pack of cigarettes. The device has convinced me.
Of course, since then, a lot has changed technologically. Now we have so many of these small and useful comms devices. The range of functions has also increased significantly. While the basic functions are mostly the same for many of the GPS messengers. The difference between the messengers is often in the useful additional functions some offer, such as two way communication, weather data, maps, indvidual messsages, connectivity to smartfones etc., live tracking, flashlight function, compass, calendar, sun and moon times, stopwatch or alarm clock, integrated altimeter and much more. Also some devices offer different techniques for example for the emergency call, such as several escalation levels for the emergency call and various alarms (crash, dead man function). So it really depends on what you are looking for. The market today offers a wide range of different devices.
It also depends on the region you go. For example, not all devices are available everywhere or are part of the official rescue chain (for example PLBs as another SOS device). I would really take a close look at all available devices before deciding. If you are only interested in comparing SPOT X and inReach Mini, then I would take for example a close look at the following points:
SPOT devices using the Globalstar network provides coverage but not everywhere. Some areas have no coverage or limited coverage. For example, parts of the Indian subcontinent, popular with some overlanders, and parts of Africa are not covered with regard to SOS and 1way messaging. There are different zones, for example 2way messaging has other coverage areas. It's best to check carefully with your travel plans to see if the destination area is covered. Coverage map was already shown above and can be found also here:
SPOT Satellite Coverage Map | Saved by SPOT
Garmin inReach uses the well-known Iridium network which offers worldwide coverage. Also, other devices such as Bivy or Somewhere use the Iridium network. With regard to Iridium there are only some restrictions, here due to embargo restrictions (e.g. Iran and Sudan as far as I know). Btw, I recently came across another device, the ProteGear A*LIVE device which works also on the basis of Iridium and has an additional connectivity feature, it combines satellite and cell phone network. It was developed by a German company especially for mountaineers. Even has a deadman function. I don´t know if it is available in other markets.
In addition, I would look at the combinability with other devices. For example, if you already use Garmin devices, then the inReach has possibilities to connect with other Garmin products.
Otherwise, I would just take a look at the devices that are on the shortlist and hold them in my hand. It's like a radio or a telephone, not everyone gets along well with every system, the feel, the operation, etc.
Exciting and versatile topic. Looking forward to the further exchange of experiences with the devices here.
