If your primary concern is emergency communications I would suggest the SPOT device over the HT. Two primary reasons:

The SPOT is relies on satellite communications, and in most cases you will be in the line of sight of a satellite. The HT relies on line of site communications and depending on topography and propogation your range is limited, especially with the limited power output of the HT.

The second reason is coverage. Someone is always watching for comms on the SPOT network. With Ham transmissions it's hit or miss that anyone is listening to the particular frequency on which you might be broadcasting.

If you want the two-way comms that Ham radio provides, and depending on your license type I'd suggest an HF or all mode portable like the 706MKII. That type of radio uses high frequency comms which can carry much greater distances and there are agreed upon freqs that are monitored 24/7.

Prices seem to be coming down on the PLB's so there's hope that they can compete with the SPOT type of product. Doug has some really good info on both on the ETS home page.

Andy