I'm shooting All i-frames with Canon 5D Mark 3..will Kingston 600x write speed be fast enough to avoid buffering? How many minutes of video can I record in All i- frames? Do you have 64GB cards?
I would not buy these cards. I purchased them in 2010 and they were not even as fast as the 300X cards from Sandisk and other vendors. My review on the card is on the Adorama site. Maybe they are improved now but I tested with multiple Canon cameras. doram was great to take the card back. I will say that I do have a 600x Lexar card and it does perform at the 600x speed. When shooting raw it will buffer on the 5DIII but I don't think you would see much of any buffer delay with JPG only.
Checkout robgalbraith web site benchmarking actual cards on each camera model. I tried to link it but Adorama would not allow it.