Review on SanDisk 16GB 60MB/s Extreme Compact Flash Card SDCFX-016G-A61: Reliable Storage Solution for High-Speed Data Transfer (US Retail Package) by Adam Hutchinson

If you're wondering whether the extreme series from Sandisk is worth the money, then it is. I've been using this card for over a year (with a Canon 5DMKII) and haven't had any issues with data corruption or data loss. In terms of performance, of course, the 5DII only shoots at no more than 4 frames per second, but it is large. However, I never feel like I have to wait for the card to be written when taking a series of pictures. The transfer speed to my Macbook is reasonable considering the amount of data coming from the card. Extreme professional card is much more expensive. . If you hesitate, buy both and see if you notice a difference that impacts your workflow.