You can read and "type" messages on the Messenger. "Typing" involves selecting one letter at a time from a long list of available characters. This is the same mechanism as on the M2. Because of the small screen, reading messages involves a fair number of button pushes and extensive scrolling (for all but the shortest messages). This is somewhat uglier than on the M2, which has a larger screen.

There are 4 hard buttons (plus SOS) on the Messenger. Power on the right edge. OK, left arrow, right arrow on the bottom edge.

Like the Mini2, the Messenger is easier to use with a paired phone. The mobile apps are different though. M1 uses the old Earthmate app; M2 uses Explore; Messenger uses Messenger. A paired wearable (any one of several Garmin watches) can also be helpful.

One important difference between the Minis and the Messenger (and their associated mobile apps) is that the Messenger has NO mapping capability whatever. The Minis have no real maps, but they do have a blank "map page" which shows your track. Explore and Earthmate have maps and show data from the paired device. None of that exists for the Messenger. The Messenger is for messaging and tracking, not for mapping.

If it matters to you, the M2 can record a more detailed track. This is not sent via satellite. It is only accessible when you sync (via the Explore app). AFAIK, the Messenger does not have this feature. It DOES record something (mysterious) for use with TracBack - but it is not available as an "activity" the way it is on the M2.

The only mounting option for the Messenger is a lanyard attachment point on the lower left corner. Lots of people have rolled their own. But it's really not all that necessary (see below regarding antenna). That said, IMO, the Messenger is every bit as rugged as the Minis.

One significant advantage to the Messenger is that it apparently has a much better antenna than the Minis. It acquires a GPS fix more quickly. It appears to connect to the Iridium network more reliably. Overall, this means that you can just carry the Messenger in your hip pocket. No need to mount it high on your shoulder as with the Minis.

I don't have any experience with ANT+ pairing (used with a watch). Doubt that it could be worse than the Minis, though.

It's difficult to compare "claimed" battery life. The marketing smoke has too many "qualifications". IMO, in real use, it appears that the Messenger has an edge over the M2 in battery life.

The subscription cost is the same regardless of device (for the same level of subscription). The difference in cost (direct from Garmin) is $100. The M2 is $400. The Messenger is $300.

thank you, i just wasn't sure if there was way to type messeg on device itself (in case phone died,etc) - because it was always said its greate with phone messenger app etc. - but this actually makes good information.
maps i don't really need (got epix 2) so that i'm sorted - it's mostly for the pourpose to be able to contact wife etc - lets say we agreed back at 4pm, and there is delay etc, so she woouldn't worry or me.

(but it does sound like messenger would be a good choice too) - shame is we do like the look of mini2 better :D

in uk they cost 349 and 249, so for 2 it would be 700 vs 500£

so if messenger is able to send tracking point every 10min, where are they displayed if it doesn't have maps? 

Sent track points appears in (more or less) real time on the Map tab in MapShare or your account at explore.garmin.com. 

For the M2, they appear (I believe) in the Explore app as well as on the web site.

For the Messenger, it's web site only. in the Messenger app, it is possible to map a message if the message has coordinates. AFAIK, it's not possible to do that with a sent track point. But I could have missed something. The Messenger app is definitely slanted towards messaging, not mapping. The ability to map a message is buried in a way that make it very hard to discover. Track points might also be there, but so well buried that I missed it.

The bitterness of lost functionality far outlasts the sweetness of low price...

but your not really loosing much are u? 

The messenger (for messages/SOS) together with an Epix 2 (for navigation/maps/orientation) is a great combination. If you compare the messenger with a mini 2 from the stand alone device use side, the mini 2 would be the better choice. But everybody may see this different…

I have a messenger and an Epix 2. 

I also went for the messenger as I already have a Fenix 7 - battery life and reverse loading (it can give a little bit of charge to your phone for example) at a lower price were the arguments for me. I do my routing/ planning always with my Fenix, that has extensive trackbac/ routing features, much more than the breadcrumb line on the mini 2. 

Be sure you understand the limitations of reverse charging before you depend on it in the field. I don't remember the details. But IIRC, but there are limitations around the minimum remaining charge on the Messenger, as well as the charge rate/duration?

Thanks for the advice. As far as I got from the reviews etc it automatically stops, so that it doesn’t completely drain the Inreach. I will sure test this feature before. 

Have already tested it and it is working as described in the manual:

Using Reverse Charging