I have had very sporadic success with SPOT beacons, which use the Globalstar network. I have hod near 100% success with the Delorme In Reach, which uses the Iridium network. I have even used them side by side in mountains, forest, and canyons in the continental U.S. I removed the SPOT from my tool kit and went entirely with In Reach. I am not sure how this will work out with the data link, however.