Yeah on stock I would get like 4-5hrs at best now I can last solid 7hrs so to answer your questions the more mAh the more power you can store in it. The trick I have found is not to let go to 0 more like 10 or 20 % before a full charge.
As for the extra charger its neat to take it on the go but I use my cradle charger for home recharging.
I think the 1800mAh Samsung battery is overrated just like the expensive Seido Extended Battery. The 1500mAh and this one both are made in china except this one might be third party because it does have www.chichitec.com printed in the back cover but in the end its just a battery with 200mAh more than Samsung. I might just have to buy this OEM Samsung 1800mAh battery that everyone praises just to see the difference.
Anyway this is just for those who want to have a little bit extra without the bulge of a extended battery cover. I am happy with it and just wanted to share and try it out has suggested in my other thread by a fellow member.
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