FRS/unlicensed low-power UHF radio is OK for short range comms and even the inexpensive stuff sold nowadays is relatively good at what it does. But its main purpose is two-way communication at a prearranged frequency/channel, e.g. between two groups of hikers at short distances.

Other than limited range, the main problem with FRS radio is that you're limited to a small number of channels within the unlicensed band. Do your local SAR teams routinely check those channels? I don't know but it's not standard procedure where I live simply because FRS radio is not used by hikers and outdoorsmen on a very wide scale. Then again, some local SAR services do use FRS radio for backup at least, so in that case you might be in luck.

A decent FRS handheld can be a useful asset, but a lone individual counting on radio to call in SAR services or outside support would be far better equipped with a "serious" VHF/UHF handheld transceiver. Obviously, that requires a proper ham license (Technician class or higher), but that's pretty easy to get nowadays.

If you go that way, there are many good, inexpensive compact VHF/UHF handhelds available today. Such as the Kenwood TH-F6A: http://www.kenwoodusa.com/communications/amateur_radio/portables/th-f6a

A compact VHF/UHF transceiver weighs little more than a cheap FRS radio, but you get many, many more options, better antenna, lots more output power (5W), you can tune to a wide frequency range and the effective range is much better.