You really want both. PLBs will work continuously for days. But with so many false alarms SAR agencies want second verification. Which can be as simple as filin

You really want both. PLBs will work continuously for days. But with so many false alarms SAR agencies want second verification. Which can be as simple as filing a travel plan and letting relatives know your hiking area. Or pop the plb and then call SAR on your sat phone to say yes this is not a false alarm.