I am a long-time search and rescue technician in Colorado. I got my ham license expressly for SAR work. The short answer is that amateur radio works great in some locations; not at all in others. We use a combination of emergency services radios, amateur radio, and cell phones. We have satellite phones available but I don't recall ever using them.
Personally, I would recommend a SPOT beacon. The newer ones allow you to signal a 911-level emergency, a non-emergent help signal, or an OK signal, along with GPS coordinates. They are lighter than ham HTs and will work in more locations.
Top Ten Things Overheard At The ANSI C Draft Committee Meetings: (9) Dammit, little-endian systems *are* more consistent!