I have a Sandisk Extreme 32Gb USB which has 90Mb/s write speeds. I also have a 64Gb Sandisk Ultra, its not as fast. I saw the extreme win a USB flash drive shootout.
High-speed USB 3.1 (Gen 1) performance of up to 200MB/s read and up to 150MB/s write
Transfers files to drive up to 35X faster than standard USB 2.0 drives, so you can quickly transfer and go
Transfer a 4K movie in less than 40 seconds. Transfer 1000 photos in less than 60 seconds
USB 3.1/USB 3.0 enabled (backward-compatible with USB 2.0)
Operating temperature is 0 degree to 35 degree in celsius. Storage temperature is minus 10 degree to 70 degree in celsius"