I purchased a McMurdo Fast Find 210 earlier this year both for my safety and my Mom's peace of mind. I had no idea just how worried she would be when I went out, especially by myself, until my Dad told me. I felt like such a heal.

Anyway, my thought process in selection was this:
major tree cover in most of the areas I hike; I doubted anyone would be tracking my progress; I didn't think the yearly fee was worth it, however if I were to go out more often, I might have been convinced it was worth it; and I reviewed the reliability of the Spot and PLBs and decided that the reliability of the PLB was better for both me and my Mom.

However, if you aren't in a hurry, heed the advice given earlier and wait for the fall review of the new Spot.