i like chichitec's slim extended battery, bought 2 of them with a wall chager for $30 a while back, 1900mAh each. One of them lasts me 2 days but I full charge at night out of habit and not wanting to be stuck without phone on 2nd day even though I only reach 60-70% after first day lol
Mugen batteries are the best. They are the only extended slim batteries I have ever tried that actually live up to the name extended and outperform the stock batt. I have had 4 of their batteries for various devices and this week I just got the first for my Rhod and what a difference! Don't know why I waited so long to get one... I guess the rhod was just supposed to tie me over til WP7 came out... but now it looks like I'm trying to hold out for windows 8 (or 64bit cpu).
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