works well

When you’re shopping for a solar phone charger, there are a few things to keep in mind to make sure you get the right one for your needs, including:

You want to make sure the charger you get is powerful enough to charge your devices. If you’re only looking to charge one smartphone, a solar phone charger with a lower power output can work for you. 

If you need something that can charge multiple devices or larger electronics like tablets, you’ll want a solar phone charger with more power. A wattage between 10 watts and 15 watts of power is a good rule of thumb when looking for a solar phone charger. Since this one comes in at Solar power: 6W / 1A... its not on the higher end, so don't expect a fast charge. 

25000mAh is a good size hold for a power bank. Since the charging speed is slow, at least it has a good amount of reserve to hold the juice. 

I gave it 4 stars because its got a nice fold up set of panels. I wish it charged faster, but it is what it is. They even say under the q&a about it that Usually, it needs 40-45hrs to full charge by the direct sunlight.
 

Yikes. That's a long time. 

I've only used it once and haven't had a chance to recharge it, so I can't tell you about long term... only my first go 'round with it.