Solar USB chargers

[grungeant (Anthony)]

I'm curious as to if solar power USB chargers are worth while?
I was looking at ones that look kind of like a real bulky smart phone. They sell them in truck stops and stuff.
I think they have battery packs that get charged by the sun, then the internal battery charges your device?
I also saw one that unfolds like a big tri-fold wallet and is fairly flat, but has a bigger panel area and it can be pinned to the top of a backpack when you're walking around. It says it requires 2AA batteries.

How do you interpret what's good by the specs other than higher numbers is better?
Realistically how well do they work?
If you have your tablet or phone plugged into one how fast will it charge, and can you use the device when it's charging or does it have to be off?

[Beetleboi -Greg-]

You get what you pay for. Matt had one they you can pre charge at home. Then you can charge it with the sun. Most of these solar chargers (correct me if I'm wrong) are for emergency purposes. So don't expect them to comptely charge your phone in half an hour.

If your talking about using it for camping, with your bus? I'd get a couple deep cycles, or 1 if you just need to charge phones, and run LEDs.