I bought some inexpensive SanDisk Cruzer Glide 16GB USB sticks from Walmart last year. Cheap. Today I copied the CentOS 8 installation image onto one. time sudo dd if=CentOS-8-x86_64-1905-dvd1.iso of=/dev/sdg oflag=direct bs=16M (I used a USB 3 port on my dessktop.) It seemed to take a long time, so I did this to see if anything was happening (the dd process' PID was 29047): sudo kill -s USER1 29047 Yes, there was progress, but not as much as I would expect. The final statistics were: 425+1 records in 425+1 records out 7135559680 bytes (7.1 GB, 6.6 GiB) copied, 1560.63 s, 4.6 MB/s real 26m4.152s user 0m0.072s sys 0m4.706s This amounts to about 4.56 MB/s. That's even less than the poor Average Sustained Write Speed 7.64 MB/s reported here: <https://usb.userbenchmark.com/SpeedTest/2718/SanDisk-Cruzer-Glide> Note: this stick hasn't been written to often. It should not be near the end of its life (that could slow down a flash device).