SanDisk goes conservative with first SDXC card
The company takes advantage of the format's higher capacity, but keeps it slow in order to keep it (relatively) cheap.
While some people are clamoring for higher-capacity SD cards, few need--or want to pay for--the extra video-recording speed. Panasonic, for example, will be issuing its first 64GB SDXC as a Class 10, 22-megabyte-per-second version card for almost $600; however, SanDisk announced its first 64GB card at a slower Class 4, 15MBps for the more attractive price of $349.99.
True, only products announced since January--and only some of those--support the new SDXC standard, but even in a lot of the newer cameras and camcorders, Class 4 is sufficient for video recording. However, that 15MBps speed might slow you down when bursting in a midrange dSLR, which increasingly support SD media. Overall, I think going for the slower, cheaper memory is the right move for most people for now. Furthermore, if you just bought a brand-new, SDXC-supporting device, you can get that extra capacity today. According to SanDisk, it's shipping the cards now. I believe makes it the first SDXC card available, despite prior announcements from Panasonic and Toshiba.