Got my SE a few weeks ago from snowbigdeal & took about 7.5 seconds to sell my inreach to a friend!
Been using it... interface is a tad tedious, I'd say it's a bit smoother than entering place names into a garmin 60 series GPS. Not fast, but not "hard" either...
LOVE the 2 way on this... so much smoother than using the phone, you can send someone a text, and then a little later tell the SE to check for messages & it's there in a second. (it normally checks for messages every 5 minutes, to save battery, but during a conversation it's real easy to use)
It still links to the phone if you want a bigger screen, easier typing, maps, all that stuff... but for the essentials, and having a required conversation with someone, this is a huge step up.
As to maps, I've looked at it & don't think you can download sat... just topo. Keep in mind, you can still download google maps in your phone. I just don't really use this as a mapping device (I have a couple times though), it's more like a cell phone for me. For just mapping though, you can just use the cell with GM & save the inreach batteries.