A bit disappointed at first ... but ...

It is sold to two outputs:
5V 2.4A "iSmart" (10,8W)
5V 2.1A "iSmart" (10,2W).
Input:
5V 1.5A
The battery is not accessible, and thus not replaceable.
(Battery mainly tested with the shield portable tablet that has 5.2V 2.1A charger (10,92W))

Count virtually 10-12h to recharge it when it is dry with dry, you plug it into a 1A charger or a more powerful charger. (Warning, it asks 1.5A max input).
Purely personal feeling: It seems better hold a charge when he was charged with low current (1A)
Or I have a feeling he can not bear to be loaded on a port Usb "iSmart" (I also have a RAVPower transformer that has this feature).

He has had a small heating time (about 4 or 5 loading and unloading) for its operation becomes optimal.
Initially, when it was fully charged, the 2.4A output was not really convincing.
My tablet still lost battery while connected over if I did run a "foodie" game resources.
But now, the tablet manages to recharge. However, if initially it was 20% of battery, and I continue to use it while she charge, it will rise only 60 see 70%. (This tablet is recognized consumes more battery power)
By cons, if I recharge "standby", I think it is possible to recharge 1.5 times.

For iPhone 4S, 5C .. Allow 4 or 5 full recharges if such remains :) yesterday.
For iPad 3 (New iPad), 2 see 2.5 full recharges, even if you do not use it in parallel.

Is much like an external hard drive, and the quality / finish looks at the appointment.