I have a Brunton Restore, and I like it good enough (I know there are better ones on the market).http://store.bruntonoutdoor.com/portable-power/panels-and-chargers/restore-trade-black/
Its nice to have the solar panal AND internal battery, so you at least have a bit of a charge even if it is cloudy and rainy your whole trip.
I've charged lots of stuff in my tent at night, and it will slowly drain the battery.
The other day I charged my phone during daylight hours, and in One Hour of sun, I brought my smart phone from 11% battery to 44% battery and the internal battery of the solar charger still said it was full! I'm sure if I'd let it sit for longer my phone would have been fully charged (I was heading home the next day so did not really care)