My first trip with the SPOT was to the Rossport,Canada Shore of Lake Superior. I have also used in Lake Superior Provincial Park, Straits of Mackinac, the Picture Rocks, and also Ohiopyle, PA. It is a great way to notify your family, and co-workers of your status. With the press of a button they get an email or text message telling them that I am okay and my GPS location. I have programmed in my wife's, my brother's and my daughters' cell phone numbers into the unit. Every paddling day when I get off the water, I send out a message with the OK function and their cellphones receive a text message; they really like hearing from me.
The unit also has two functions for emergency situations. I have never had an emergency so I cannot vouch for the response, but I imagine it is as good or better than an EPIRB. For the HELP function, I have programmed in a few friends, one is a policeman, and they will be notified that I need help and my GPS location. If it were a very bad emergency I would send out a distress call with the 911 function. But as I said, I have never had an emergency and cannot comment on the response time.
The unit is very competitively priced for the features, especially when compared with an EPIRB or Satellite phone. I use two AA lithium ion batteries. I have sent many messages and have had no battery problems and have been using the same batteries for over a year.
Two small complaints: which is why I did not give it a 10.
One is that it takes about 20 minutes to send out a message. I will get off the water and send my message while I am setting up camp. After a little while, I will check to see that my message has been sent. I am usually in no big hurry, but in an emergency situation a faster response time would be desired. Of course, prior to having a SPOT I had no way at all to send an emergency message, so compared to that situation 20 minutes is very fast.
The other is that they do not cover Hawaii, South and Central Africa, and much of Central Asia. Excepting Hawaii, I have never been to these areas, but I currently have a friend in Malawi and my daughter may be going to Central Asia and I would feel better if they had a SPOT. I am always planning a paddling trip to Hawaii and would like to be able to use it in that location.
I fail to see why SPOT cannot have a full Global network when Iridium has a fully global satellite phone network. Again it is a small complaint since I have had coverage everywhere I have paddled since buying the unit.