Go for the III. You will not see any meaningful speed difference.
I would never use just one big card. just imagine it breaks or you lose it, you´d lose a lot of data.
I have always had the largest available cards in my camera, never carried around any 2nd cards and thus never lost a second card
Meaning: if you buy a Sandisk card and you put it into your camera and never take it out there is zero risk that it will get lost (unless you lose the camera) and almost zero risk that it will get broken. It's much easier to lose a single card outside the camera or to break it by pulling/pushing it out/in
And as a natural precaution download your images as soon as a computer is near
The only time I ever lost images was my first and last try to use a Transcend 4GB SD (not SD-HC
) card in my D80 Never ever try this
Thomas (beware: Nikon-fanboy and moderator!) My Lens Reviews
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