I have one. The battery definetly adds alot of weight too it. Also since the phone wasnt made for a bigger battery windows phone displays the battery level incorrectly and you need to restart it everytime you want to see correct battery level. Also takes forever to charge it.
Also the 3900mah is false advertising.
Their 2x the size the original 2x1280= 2560mah.
Your better getting a spare
Nokia N97 < HTC HD2 > HTC HD7 < Samsung Omnia 7 < HTC Titan < Galaxy S III < Galaxy Note II
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