I had a Lexar 32GB 1000x card fail awhile back and spoke with various people at Lexar about it. I had been using an older Sandisk FW800 card reader, as my MAC location laptop only had Firewire 800 and not USB3. Lexar, in no uncertain terms informed me that all their UDMA 7 cards must be downloaded using a UDMA 7 compliant card reader - they didn't care which brand, just UDMA 7. They said that using a non-UDMA card reader might not cause the card to fail immediately, but it will eventually - no if, and's or buts. They replaced my card N/C. I posted about this awhile back and got flamed by someone claiming to be an engineer, blah, blah, blah, but the fact is, Lexar themselves is saying this, not me. So, I don't know if the card reader really is/was the entire problem, but I'm sure not taking a chance. I'm using a new UDMA card reader and suffering with the slower transfer times as it's bottlenecking into the USB2 port, but better that than going against Lexar's directive and potentially wrecking a card and losing all my images.