I had my share of probs with cards. But my experience is, if it works, it works. These cards are physically so simple, that they're probably the most reliable part of your cam. More chances you lose one, then them going haywire.
If probs occur, that's most likely the readers (I have one of those
Oh, and by the way: I encourage everybody to download the latest pics, once a computer is within reach. I only delete the pics on my card when I have a backup of those on my computer.
To make sure your card is ok, before giving over your valuable photos to it, just fill it up to the brim from your computer, add a few (hundred) test-shots, erase some in camera, then from your computer (via USB), then random open some files. If probs are likely to occur, they will have by now!
buy a 4GB SD-card that is not to the SDHC standard...
Thomas (beware: Nikon-fanboy and moderator!) My Lens Reviews
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