As far as the solar panel and the charging capability goes I would give this about a 4 out of 5. This is great for anyone who is always outdoors or loves to get out and just walk for a long period of time. It does take awhile to charge up a phone and to be able to charge it at a steady rate you would need to have the phone turned off and not in use. It would also need direct sunlight to shine on the whole panel so sitting in shade or having it behind a window would slow or even completely stop the charge. I would also recommend only using the Micro USB cable provided seeing as it charges the device the best when plugged into the panel. Other cables seem to fall short or dont charge the device at all. On a comfort level I would give it about a 3.5 out of 5. When youre out in the sun and have a solar panel on your back you can definitely feel the heat gather throughout the bag. Taking it on and off is recommended due to the warmth it brings to your back especially during the summer days. Overall the straps arent as padded as I would prefer and the clips that bring the straps closer together fit tight and arent very comfortable. Ultilization of space and quality of material would give it a 4.5. Big enough pockets to fit my 17 inch laptop in and still have room for the cables, water, and a book, maybe even more if Ireally wanted to. The only problem I have had is that the bungie cord to one of the side pockets has detached, leaving the pocket open and unable to close.

A nice sized backpack for school of light hiking. The solar panel needs direct sunlight for optimum charging and even then charge times are long, I find it is best for keeping a backup juice pack charged but have charged my Samsung galaxy 6 with it, When there are no other sources this is the best I got.

I love the light weight of this backpack and the immense amount of space in it, however, the reason for buying it was for the solar panel feature. I actually wrote an E-Mail to the manufacturing company regarding this because I have not been able to get it to charge up. They replied that it really has to charge up under DIRECT SUNLIGHT. Well, I live in an apartment in Brooklyn with the next door apt's brick walls facing my windows so I cannot get it to charge. If you are a teenager that is outside a lot or a hiker or something outdoorsy, I would definitely recommend this though. Besides that it is a nice light and roomy backpack and I bought two on Deal of The Day so I only spend $39 on each, however, I am considering returning one of them for my own situation... I am just never outside in sunlight. :(

Pros: 1. Lightweight (this is almost worth all the other issues... it Is incredibky light fir one that really holds a lot) 2. Lots of space Cons: 1. Cannot get it to charge (solar panel not working?) 2. Zipper for back part of bag gets caught in the fabric flap along the zipper. 3. Bungee strap for the left side cup holder snapped from one side (inside the sleeve of the cord) on the first day when trying to tighten it around my travel mug Note: I bought this on Deal of the Day for $39.99... green was out. They just went back on DofD so I bought the green one too... supposed to be the same, but the description for the green one says "interlocking zippers"... I will review it too when ot gets here. I also bought the Samsonite Tectonic that holds up to a 17" laptop... that one Is nice too, but not quite as light, but it hold a lot and has lots of little spaces for your things. I WOULD RECOMMEND TO FRIEND ONLY ON DEAL OF THE DAY AND even if you could get the charge to wirk, I would not value this at $99.99

I haven't used this bag yet. Planning on using it for an upcoming trip to Asia. I actually expected it to have a power pack of some sort that I could charge and keep charged (a reserve battery) and charge my electronics from it when needed but turns out I have to plug the electronic directly into the solar panel and have it in the sunlight to charge. Perhaps it will charge a backup power pack, but I haven't tried it yet. Was hoping not to have to carry extra devices with me. I do like the configuration of the bag. It has plenty of pockets and places for water bottle. etc. I'm a bit concerned about the solar panel on the back taking a beating and how it will hold up. Only time will tell!