The speed of the flash memory used, the memory controller used and the read write block sizes.
For most folk they can't change that so you hit review sites to pick a good one. Currently the champ is this one.
-> http://thewirecutter.com/reviews/the-best-usb-3-0-thumb-drive/
All of my pc's ports are USB 3.0 and I'm just wondering what aspects of the host effect a flashdrives read/write speeds, and how I can determine what these are for my USB 3.0 host.

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