[MattKing]

I have the Pro so I have interchangeable backs. I've never handled one of the earlier ones.
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I don't have, nor have I used, one of the left hand grips. I have the winder grip, which is a right hand grip. The camera handles great with it, even if it is a bit big and heavy.

The right hand motor grip for the older versions (not the Pro or Super) is very large and noisy, and it can be hard to find one that includes the necessary coupler.

Rumour has it though that the thumb operated winder designed for the 645e may work with some of the older models.