The brand Ambrane is quite good, but this power bank doesnt satisfy the needs of a good portable charging alternative. It has a Li-ion battery, with a capacity of 10500 mAh, which should be quite good, but unfortunately, it doesnt give a quick charge, and the rate of discharging is more than that of charging. The design is cool, the capacity is sufficient, but the main problem is it gets self-charged very very slowly, and is quite hectic on long journeys.
So, from my point of view, seeing the cost of about Rs. 1200-1250/-, this doesnt seem to fulfill the needs of an average customer.