treadi, my bit of bundu is the less inhabited bits of South Africa. We get good FR24 at airline cruising altitude and most areas have good connectivity down to around 8000', where I spend my time these days.
It seems there are enough keen FR24'ers in SA that they have installed the receivers in their home towns, so we have pretty good coverage.
But I take your point, this relies on line of sight for position finding, unlike the SPOT or Garmin or similar satellite based safety systems.