Hopefully Paul could help me think through this-

I am an avid outdoors person and really like the ability to use the BT Freedom GPS unit when I hike, kayak, etc.

However, when I got on multi-day trips, I am worried my GPS will die after only one days use. I really want to have the ability to plug in either a solar-charger on my pack or a AA-to-USB solution to charge it.

Is there a power output I should be aware of? What challenges do you all see?

Thanks!