I was in the same situation a month or so ago- trying to decide on which GPS/ Personal Locator Beacon to purchase. I ended up with the Explorer+.
My reasons are that I wanted:
1) A back up GPS to my phone
2) A PLB/ SOS device in case of emergency.
The Explorer Plus takes care of both of those things in one unit and also has satellite text capability (it’s slow, but works).
Used it once so far and was happy with it except for it needed to calibrate and recalibrate the compass about 4 times within 10-15 minutes. Not sure why (might be something simple- I’ll have to research), but it worked otherwise.
My wife was able to track me on her computer when she couldn’t me via Find My Iphone. And I sent a couple text messages which she received.