I have a goal zero solar charger that I've used for 2 years now. First it works, the issue is when you should be charging is generally when I'm hiking. So you land at a camp site and set up, get the charger out, middle of summer you may get an hour before thee sunlight goes down. If your at camp all day you can charge up. I like it but feel it still lacking. I'm waiting for sul flexible panels with super small batteries. Charges while hiking, stores in the batteries, charge up phone/gps at night.