http://www.cheapchips.com.au/memory/secure-digital-sd.htmGo with something that's renowned to work well as you'll be less likely to hit issues. I'd stick with a standard size SD card rather than going for Mini's or Micro's in a converter, they wont help read/write speeds and if they eject themselves a little who knows what issues you'll hit.
Memory cars SHOULD last a life time because they're solid state, no moving parts like hard disk drives, so spending money on a good one that utilises the max read/write speeds of your camera is pretty much paramount and the sole purpose of buying a memory card - bar storage of course

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