I have a Nuvi. I don't know about moisture resistance, but I'm lucky to get three hours out of a full charge. By contrast, I've got an older Garmin that gets a good eighteen hours out of a set of single AAA battery. I love the Nuvi when I use it in my car though... I'm just not crazy about it as a hiking or biking model. Too big, for one thing - and Garmin wants 89 bucks to update the maps...urgh!