In a word, yes. Of course, there are the normal limitations associated with any GPS/satphone device. Namely, you have to be outside with a clear view of the sky. What’s more, as with any of these class of 406 MHz Personal Locator Beacons, the communication is one-way only. Your friends are going to know exactly where you are… and that you’re ok… but they’re not going to be able to send you a message that says, “Honey I miss you.” As for dependability, the device has a lot going for it. This same network (GlobalStar’s simplex network, that is) is currently handling ship locator beacons and lots of other tracking devices to the tune of some 6 million messages per month with a reliability rate said to be close to 95%. Just in case, any message you queue up on your Spot Messenger is automatically re-sent 2 extra times for a total of 3 instances (the duplicates are dropped in Milptas if the original got through ok). So… barring any financial difficulties at GlobalStar (Hey, even Iridium had trouble staying afloat), the device should be good to go for years. There are still other caveats, however. Because it’s relying on the GlobalStar satphone simplex network, there are some limitations as to location. For example, forget the southern half of Africa, much of India, regions to the north of India, and even northern Alaska [updated: See “comment” below for more on this]. So if you’re heading to one of those locations, you definitely need to get this device in hand and try it there prior to depending on it for a life or death situation. (If it doesn’t work for your geographic area, my guess is they’d refund your money.)