Just some additional info...
FYI, Spot's Global Phone
coverage maps show "extended service" (poor/sporadic signals) in Mexico
....as well as requiring "roaming charges" of $1.49/min in Mexico
/ central Amer.
And, they show NO coverage in Central Amer. at all...
So, again, not sure where the original poster was planning on sailing / cruising....but for those heading to Mexico and/or Central Amer, it appears that the Spot Global Phone
is not "global" at all!!
And, for those in Europe
contiguous, Thuryra is a good service
But, for everyone else....it's Iridium
or INMARSAT (or HF Radio)...