Yeah, you’re going to enjoy much faster messaging, although I’d guess that InReach has a long range, what with a satellite and all to help.
Once you’ve got an idea of what the individual units can do, adding more gives significant advanatges. You can then leave one in a high location to provide better range by using the hopping feature.
As for the caravan, if the roof is metal it provides impressive performance. I have one mounted in an old plastic pickle jar that I added a magnet to the jar lid and painted it green to match the truck. More on this in my Urbana thread.
If you want to lend them out, Unpair them first (in Settings), have your friends get the App on their phone then you can have them Pair to them. Same thing in reverse, plus all your data should be memorized in the App.