Regarding the manufacturer.
All SD cards are made to the same standard:
http://www.sdcard.org/
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Faster cards
If a camera needs a faster card to meet its specifications....the camera manufacturer will specify that in their User's Manual.
Will a faster card improve performance of a camera?
Not likely.
Notice that the makers of the faster card never state that you will see any benefits from the faster more expensive card.
From reports on some cameras, you may (or may not) see an improvement in "start-up" time, if you are using a card that is larger than 128 meg. Start-up time is from the time you turn-on the camera until it is ready to shoot.
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Before my next long trip I will buy a 1 gig SD card. I am thrilled at how the prices are falling, they're cheaper than my 128MB MMC was a few years ago. However, I want to know about speed. How fast does the card need to be for optimal function (I have a Casio Ex-Z50)? Is faster always better, or at some point does the limiting speed become the camera? I'll pay more for better and faster performance, but I don't want to pay for capabilities my camera will never be able to take advantage of. Also, what are you guys' thoughts on the best SD card manufacturers?
(PS I thought I'd started this thread already, but I could never find it, so if it exists and this is a double I'm sorry).

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