Removing/replacing the battery didn't solve sluggishness for me :( Then again, I'm on a BES, with IT Policy set to enable content protection...
I haven't dropped calls yet, but did initially see the signal bars varying a lot, and switching to GSM... seems more stable and consistent now.
I haven't tried UMA yet..
Work T-Mobile 8900, 8320, 8120 & 8220 - Personal Verizon 9550, 9630, 9530, 8130 & 8330
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