Bought a couple of these a few months ago and it's been blazing fast and reliable (to full capacity) in both 5Dii and 7D. $59.99 + $2.00 shipping. IMO it's the best deal around.
Type: Compact Flash (CF)
With read speed at 80MB/sec and write speed at 50MB/sec
Four-channel support (Ultra DMA mode 0~6 , IDE PIO mode 6, MDMA 0~4)
Low power consumption and RoHS compliant
Support Error Correcting Code (ECC) function to detect and correct errors