Over at MacPerformanceGuide, I’ve organized three recent card tests:
They’re all excellent, but whereas in the past I trended to using CompactFlash, that standard has lagged in both speed and capacity, so my current preferred card is the high speed Lexar 2000X 64GB SDXC.
But even though it’s not the fastest card, I also like the Lexar 1000X 256GB SDXC for a simple reason: I can make a backup of all critical data and stick it into my wallet and not even notice it being there. Very cool.
I hugely prefer high-capacity cards (64GB) because in the field there is no need to erase them, thus they are an additional backup over and above downloading the day’s shoot (and backing that up too). Aside from cost, I’d be buying 128GB or larger cards for that reason, but for now 64GB serves me amply for most of my trips (not filling up).