Agree. SanDisk, but also because of RescuePro
I also use the SanDisk cards in my 5D, but one perhaps overlooked advantage is that I get a small CD with a copy of RescuePro software on it as part of the purchase of the SanDisk card. I have used this software now, twice, to rescue images from a card where formatting by either a PC/MAC went awry, or the camera format got frazzled. In both instances RescuePro, running on my Mac, was able to locate the missing images, AND MORE FROM PAST erasures, so I am VERY pleased with this PLUS with the purchase of a card from SanDisk. Just thought you might find that interesting.