I also use a SPOT-2 (basic unit). At $100 for the unit + $100 annual subscription costs, the price isn't too abusive.

Here's a recent review cited on one of our local GPS store websites:
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And some user comments from another local GPS store (not all positive)
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My own unit has worked perfectly.

Some people need the ability to send text messages, but the basic unit has all the functionality I need.  You can send 4 different messages: "I'm OK" "SOS" "Send Help" and "Custom", all of which are tagged with a map location. I use "Custom" to mean "Schedule delay, either due to stormy weather or more fish than I can eat in one day." With some imagination (time stamp, sending multiple messages etc) you could probably encode a whole bunch of preselected "custom messages" in this one button.

If all you really want is something to call for help in an emergency, SPOT seems to work fine, and as the industry standard, you don't have to worry that the company will be gone in six months.