*** Positive ***
The 6600 mAh are a realistic value, my tablet with 7000 mAh battery is fully charged when it is almost empty.
It is also positive to note that both the input and output with 2A or 2.1A "uptodate" are. Power Bank and the connected devices are so loaded quickly.
*** Negative ***
Slightly disappointed I am about the design. White plastic in clearcoat appearance affects me somehow cheap. Design is a matter of taste, it has not hit my.
Furthermore me the supplied connection cable with round 15 cm is clearly too short. I have my Powerbank like. In another bag as the device to be charged himself and that's simply not possible with this cable
*** Conclusion ***
Price / performance are certainly in order. The Power Bank performs reliable service, but let the negative aspects just listed (where design is no shortage!) For me no better review.