I have a small 1TB flash drive. I connected it to my Mac Pro via USB 3 and was only able to transfer data at 62.1 MB/s (write speed) and 151.9 MB/s (read speed). I got almost the same result on my new Macbook Pro with (Thunderbolt) with USB 3. For comparison, my very old 128GB USB stick has a write speed of 84.2MB/s and a read speed of 132.7MB/s. My WD My Passport 2TB SSD (USB 3) achieved 919.5 MB/s writing and 898.6 MB/s reading via USB 3.
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