>What justification do camera owners have to buy one of
>these?
>
>Shooting large weddings?
>
>Shooting for extended periods? What else?
>
>And what are burdens of weight and bulk added to the camera?
>
>At my current rate, I only charge my D7000 battery once in a 3
>or 4-week span.

I spend a huge amount of time in some pretty remote locations, so 128 gigs of card space, and lots of battery are paramount. I just saw this in my D7000 manual that the supplied Lithium battery should not be used below 32F!? That precludes me from shooting 90% of my work. Another reason to use good old Alkaline batteries in the MBD11. I notice that after about 10 minutes in 20F ambient temperature, my Main battery Indicator shows almost completely drained? Ouch! During this same time the Alkaline secondary's were un-affected.

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