Anyone has some advise about power bank?

[rackak]

A newbie here, My 9100 battery now nearly drain can not support whole day using.
I want to get a spare battery and find something like power bank very popular in amazon AD like :
amazon.com /Constellations-Thunderbolt-Incredible-Blackberry-Fashionable/ dp/B00DJ3DZK2 (avoild link, delet url space when paste in IE) 5200mAh
Also Anker spare battery : amazon.com /Batteries-GT-I9300-T-Mobile-U-S-Cellular-EB-L1G6LLU /dp/ B008AGA6PK/ only 2000mAh
But it is not the original samsung replacement. And I also found many "Samsung" battery but the merchant is not the samsung company.
Which one I should bought? Do anyone use them can give me some advise ?

 

[yeputi]

Personally I tend to extended battery. I keep Galaxy nexus as my basic, using a mpj battery currently. The difference to the stock battery was very clear so that I only have to charge it every 3 days.

 

[ajack46]

Never got the need to use one, my friend though uses this one Anker E7 Battery (25,000 mAh) with his Samsung S6.