If you're looking for a low-maintenance, economical device that will get your coordinates to authorities in a last-resort situation, ACR's ResQLink+ (2) and McMurdo's Fast Find 220 (4) are good options. Both beacons are waterproof, require no service subscription and guarantee a battery shelf-life of six years. The disadvantage is that these are all-or-nothing devices, leaving no room for communicating with search and rescue beyond the initial call for help.
The Fast Find 220 comes with a floating pouch and has the lowest price tag of the four devices tested ($249, mcmurdomarine.com). It's a single-use device--you snap off the red cover to expose the antenna and the "on" button, which will activate your distress signal. Meanwhile, the ResQLink+ floats on its own, and ACR will replace it if used in an emergency situation. But be careful: The button with the power symbol sends the distress button. If you turn this unit on, the helicopter is on the way (acrartex.com, $280).
SPOT's Gen3 (1) device is the latest from one of the best-recognized names in the PLB market. Its tracking feature allows you to post coordinates to an online map at regular intervals, and the 'Check In' button provides peace of mind for your pre-programmed contacts. Since emergencies come in all degrees of severity, the Gen3 allows you to request help in non-life threatening situations or to call in the search and rescue cavalry. (findmespot.com, $170 plus service plan starting at $15/month, annual contract required).
DeLorme's inReach Explorer (3) rounded out the group with its feature-rich display and Iridium satellite connectivity. The inReach offers two-way texting to phone numbers entered on a computer before your trip. This provides welcome assurance to loved ones back home, and could prove incredibly useful during a rescue situation. With the inReach's built-in compass and downloadable topo maps, it also serves as a fully functional GPS. It will even connect to your Twitter and Facebook accounts. Update if you must, but don't cry to us if you get caught in an emergency only to find your last backcountry tweet killed your batteries (inreachdelorme.com, $370 plus service plan starting at $15/month, no annual contract required).
–More GEAR reviews from C&K.