Bought three pieces. One of them works. I have a lot of video files, each several GB, so I decided to test the drives by copying about 190GB, which is about 80% of the formatted capacity of the drive, and then using the standard shasum tool to check integrity of files after copying and momentarily ejecting the drive. Any valid storage medium should easily pass this test. Disk No. 1. Formatted in NTFS as usual. Average write speed of 40MB/s with a non-working, high-performance computer and a USB 3 port. Removed the drive, unplugged it, waited a bit, plugged it back in, ran the industry standard Shasum utility to verify the copies were identical. After about a dozen attempts, including multiple USB ports AND an attempt on a separate computer, the disc became unreadable after about 30-60 seconds. Sometimes he came back, sometimes not. Recycle Bin #2. Format it to exFAT because hey who knows right there. This one failed while formatting but for some reason I persisted and formatted again. This time the files were copied at 130MB/s, which is much faster. Eject, disconnect, wait, reconnect, run shasum, read successfully at 143MB/s. Disk #3. Format to exFAT. Writes unsuccessfully 50 seconds after the first attempt. Restored. Reformatted. 90 seconds after the second attempt failed. Restored. Reformatted. Failed on the third attempt in the 10th minute. Garbage. I think the reason is very unreliable contact between connector and drive. A light touch of your finger on disk #2 will cause it to fail immediately. This does not happen with other brands of jumpdrives. If you get one, keep your thumb on the switch, which extends the connector, while you plug it in. I suspect it has something to do with that. Here are some of the glitches I saw on disc #3.
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