Those Solio Classic 2 are fairly new. The first version were very poor workmanship and the solar capabilities were far from what claimed. Perhaps this version is better?

Are you planning to use this solar charge at home or in a BOB where you might be on foot? If on foot, finding 10 hours to charge the battery and under idea sunlight conditions would be difficult. This would be okay if you were stationary and could remember to turn the device into the sun every couple of hours.

In regards to the SLA batteries, I have a 12 volt 5Ah battery. These type batteries are good for light duty recharging such as for flashlights, phones etc but need some care so that they are neither over or undercharged. Also their weight does not lend themselves to be carrying in a backpack and when on foot. Also keep in mind that at some point, this battery will also need to be recharged and a Solio type charger is not enough.

If you are looking to learn more about batteries, solar panels etc, I have found these 2 websites to be invaluable with my research.

Batterystuff.com

Battery University