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What camera are you using that you need such a high speed card?

A 300x card will be enough even for recording video with a 5Dii.
 
I might not be answering the question directly, however I use 2X Transcend 32GB 400X with a 5D MKII (for both photography and video) and both have been flawless. I would assume the 600x version would be as good, but even faster obviously!

Additionally, they are quite affordable, just have a look at bhphoto!
 
I know Transcend and Kingston. It was a question about these 2 specific models.

Thanks
 
Ive seen a page somewhere on Canons web site thats recommends SanDisc and Lexar cards but I think thats just so SanDisc and Lexar happy that they charge extra for they're brand name. Get Transcend anyday - way cheaper and just as reliable IMO
 
I know Transcend and Kingston. It was a question about these 2 specific models.

Thanks

They are pretty similar in quality. Transcend is a well known Taiwanese brand. I would go with Transcend because they tend to be less expensive and they have a lifetime warranty.
 
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