I'm a member of the local S&R and I own a Yaesu VX-7R which is an awesome radio. I don't own a PLB, though it is on my wish list. If rescue is your main concern, then PLB wins out.
Regarding the Yaesu HT in case you decide you want to get a HAM radio in the future: I carry it when I hike and, although there are some dead spots, I generally don't have a problem pinging the main HAM repeater (and several others depending on my location).
I think you'd find that HAMs are very active; I've never had a problem trying to reach someone on a repeater. For $10.00 you can buy a small book that contains repeater frequencies for locations across the US. So when travelling, it is no problem to program your radio with local repeater frequencies.
A side-note: I'm trying to encourage more S&R people on our team to get HAM licensed since the 'standard communications' (simplex) is pathetic in the mountainous terrain we live in. We did a short field exercise in November and tested 3 configuration. The results are on my webpage if anyone is interested:
http://home.beyondbb.com/jmedlock/WMSAR_Radio_Field_Test_Results.pdfJustin