I bought some cheap NiMh 2300mAh batteries from a store here in Norway. Bought them just to test my new BG-E3, and they've been in use since. On average I've shot about half 'n half flash and not and got about 4-600 shots with 6 of those batteries.
As I'm almost exclusivly using my IS lens now and no flash, I'm getting about the same ammount of shots. IS does use a bit of power it seems
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