Some PLBs, like SPOT, have a check-in feature that lets you send a status email to a set of contacts. In the case of an emergency where all power is out -- where I live, an earthquake that knocks out everything including internet, phone, cell phone is plenty likely -- what do you think about investing in this technology for the purpose of letting family/friends know that all is okay? Obviously, in the case of SPOT, for $99/year, this would not be the only use case for it, but it seems like one reasonable usage. Any chinks in the armor here? Any reason for me to worry that if there's a disaster here, the service will also be out?

Apologies if you've discussed this before, I didn't find it.