I spent a week 10 miles off the coast of Belize on a fishing trip a dozen years ago. We stayed in a small fishing lodge (huts on stilts) on a small unnamed Cay with no one else for miles around. I made sure I had the satellite phone with me at all times. Years ago a shrimper friend took his boat about 40 miles off the Georgia coast to fish for snapper and grouper. The boat started sinking and all he had was a CB radio. Ionospheric conditions caused the normal line of sight communication to "skip" to Kansas where a trucker picked up his emergency broadcast. The trucker made a long distance call to Coast Guard Station Tybee which dispatched a helicopter to rescue the two men. Blind luck. An EPIRB would have lessened the suspense. SPOT wasn't around then. Both EPIRB and SPOT utilize satellites. I believe EPIRB uses both US and Russian satellites. Either is better than nothing, but do a google search for Spot v. Epirb before making the choice.
