Works well as it works ...

At the reception, the product works well and increased autonomy is there. However, just six months after purchase, I had the misfortune to let the battery run down completely because I had not charging point nearby. Result: the battery does not load at all, the phone was completely dead. A tower for repair confirmed to me that it is this battery Anker is involved. In short it held properly six months, and now she's dead, we have to buy another. But I do not redeem Anker, for sure.

NB: we must also know that the use of this type of battery is very badly viewed by repair centers authorized by the mobile brands is a guarantee cancellation reason (rightly or wrongly). I had nothing to do but that is perhaps not the case for everyone. Good to know.

Update 3/18/2014: After publication of my original opinion above, Anker contacted me to offer me a refund or replacement of the defective product. They have a good sense of customer service, it makes you want to let a second chance to their products. (But then the blow of the cancellation guarantee turns me some)