PLB1 could be an option. But since I am always diving in the far east countries - Indonesia/Philippines/MAdives, I wonder if they could be useful there. Any opinion
My opinion is if I'm lost at sea any where in the world, it's good to have it. I can activate it and send distress signal all the way up to the SAR satellites and let USCG or US Navy know that one of US Citizen is in trouble & need to be recued. They then can work with local SAR, like Basarnas for Indonesia to rescue me, if I'm lost in Komodo or Raja Ampat.
Here is a good thread to browse over about having PLB in Indonesia:
Safety equipment - PLB?
Another interesting post by
@IyaDiver about using PLB in Indonesia here:
Scuba diver's Personal Locator Beacon - how never to be lost at sea with an interesting CASE TO NOTE :
"A friend of mine bought exactly the same config, 210FF + custom diver cannister.
For reason unknown, his canister leaked and short circuit took place and the 210 self powered itself and made the transmission. The best part is, the 210 was in the cannister, in a dive bag and in a dive center warehouse, which I am sure its roof is not concrete but those cheapo red clay roof common in poor country like mine.
Since his unit is also registered at NOAA, hold and behold, someone from the US Navy ( or Coast Guard ) called him on his cell. It was missed call at first , twice , as my friend was on a boat ( not diving ) so it was noisy. He noted the USA prefix and twice missed calls and this must be important he thought. So he called back and was asked if he was OK and was informed that his PLB made a distress transmission bla bla bla. DANG, only USA can afford to do that !!!"
PLB1 is pretty small anyway. With a waterproof case (I used an old camera case that is waterproof down to 40m) they are smaller than a 500ml water bottle. I put the set in my BCD waist pocket along with the other safety gears.