You’ll need to define “best”
The spot cost me $120 for a year service. I get 20 messages month. .25 cents after that. Already used it on the job when the concrete mixer driver was lost and I had no cell service.. I texted the dispatch and got it straight.I used an in reach through work as a lone worker.
It is a good thing but we were told the texting and email was expensive, won't matter if you need it use it.
The advantage is the options to request help or check in without hitting an emergency SOS button.