I was able to get cell phone contact along the JMT only at Lower Cathedral Lake, Red's Meadow, Tuolumne Meadows, Forester Pass and Trail Crest Pass. The service at the above locations was weak and discontinuous, at best. I was able to let my wife know that I was still alive though. If that is all that matters, then a phone is not that heavy. If you need reliable communication, a cell phone is dead weight.

I have given some thought to getting a Spot 2 PLB although I have heard bad things about their customer service, subscription policies and reliability. My wife wants me to have something so I am giving serious thought to getting a McMurdo FastFind 210. It weighs about the same as a cell phone and will send an emergency message and homing signal. It is a one use instrument but has the life-saving features that a cell phone most likely does not have.