Summary: I also timed large file transfers with similar results to the above benchmark tests. Transcend advertises this as 400 X which is 60 MB per second then further says it is only 60 MB per second in read and is only 30 MB per second and write. Actual tests indicate that it is approximately half that speed.
Pros: It works
Cons: Performance is nowhere near what is advertised. After noting slow performance in my Nikon D 300 S, I benchmarked with ATTO and with flash memory toolkit. The memory tests at a maximum of 20 MB per second write and 32 MB per second read. This translates to 133X write speed and 200 X read speed. I am very disappointed and am returning to Newegg.