I just want to say that I am so grateful for all of you! Thank you so much for all the detailed and well thought out replies to my original question.

I have a Verizon Samsung Galaxy phone as well (that's not active). Verizon does provide overall the best coverage nationwide though at a premium over most other carriers. The idea of carrying more than one sim card is an interesting one that had not occurred to me.

Keeping my devices charged is a non issue as I will have a solar charger.