I have a Ocean Signal. I got it mainly because of it's small size. I take it on my motorbike, MTB, hunting, tramping, fishing so it has had a lot of hours being carried around. The battery needs replacing in a couple of months which costs about $250. Cheap insurance for seven years I guess.
It has a test function that you are supposed to activate periodically to make sure it is still working. I haven't had to use it in anger yet I am pleased to say.
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