I also have the mini. Its great for communicating when paired with a phone, or without if using the pre-set messages. You can have a quite a few preset messages and they don't affect your plan the same way. As for the maps, they are identical to your maps OP. The Inreach explorer still uses the DeLorme maps and has no SD capability, so no Backroads maps or other third party topo. I agree with Sharpish. Either buy the mini and a separate GPS or wait for Garmin to eventually update the product to use Garmin maps and have SD capability.
Sharpish any news on this? I got fed up of waiting and just went for the mini. I often us my phone with pre downloaded maps for GPS.