As others have noted, the write speed is a measly 12 MB/s. Read speed is okay, but not as expected or close to the advertised rated speed (e.g. less than 1/4). I tested H2testw (latest version) as well as the test built into Windows 10 and copied and moved a 1.6GB file using TeraCopy. I understand that formatting takes up some space, but the 57.7GB left over from 64GB seems like a lot, but I don't have another 64GB flash drive to compare it to. At $7.55 total, it's still a decent value for the things I'll be using it for, so I'll keep it to myself, but if you're looking for speed, then this isn't what you want. I have a SanDisk 256GB Flash which is the original USB 3 and is blowing this drive at 3.5x write speed and over 100MB/s read speed.
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