I've had no problems with Transcend, PNY or Sandisk. Also, I've found it's helpful to format the card every time you offload photos, that is, don't just delete the photos, reformat the card in the camera in which you intend to use it. I've run into folks who've had problems, & the only variable I can find is that they just delete the photos without reformatting.
Other than that, I think the size depends on your workflow. I don't travel much, so I have the habit of moving the files off the card to my PC, which is then backed up off site. I do this most days, & almost always within a day or so of shooting. This way if a card should die on me, I won't have lost very much. So (based on some good rules of thumb from other posters here) figure out how much you need to get from one shooting period (day? week? hour?) to the next & go from there. Fewer, smaller cards would also limit potential damage if one should go bad. Also, if you lag your purchases just behind the newest "largest" size, you get the best bargains, even on name brands.
Hope this is helpful.
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=5cat=
). Class 10 tend to be somewhat affordable now, so you might want to consider it. Oh and forget about a seperate speed rating some vendors tend to give their products; it's mostly marketing BS which will really cost your some extra cash without any real benefit, especially it's something like a 10MB/s class 2 card, or a 20MB/s (or even 30) class 6, a decent > =20MB/s card will have class 10 rating. Period.
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