After a lot of messing around with messages, I will try to clarify the different kinds of messages. SOS messages are a separate category with which I have no experience and want to keep it that way. I hope SOS messages don't take a lot of practice to get them to work.
Plain ol' messages are sent to any recipients with arbitrary text which you compose on the spot. You can send them from the SE standalone or from Earthmate on a paired device. They are charged against your plan.
Quick Text messages are pre-composed on the inReach or a paired device, can be edited on the spot, and are sent to any recipients. You can have any number of these. You can send them from the SE standalone or from Earthmate on a paired device. They are charged against your plan.
Preset messages must be composed on the Share website and they each include a list of one or more recipients. You get exactly three of these. Neither their text nor their recipients are available to you on the inReach nor via Earthmate. In fact, you cannot even send them via Earthmate on a paired device. They can only be sent from the SE directly where they are known only as Preset message 1, 2, and 3. Try to remember what they say and who they go to! You could cheat and carry a slip of paper with reminders, or you could keep an electronic copy on your paired device, if you have one with you. There are two ways to send the Preset messages from the SE. You can hold the X key on the SE for several seconds to see a screen with the choice of the three messages, or you can click the Preset icon on the home screen. These three messages are free and unlimited on all plans but the safety plan. In the safety plan there is no advantage in using preset messages other than convenience.
There is a fourth type of message, which instead of the user's current location includes a different location, a reference point. It also includes arbitrary user text.


