We measured transfer speeds from the TransMemory Pro 64GB Flash Drive with CrystalDiskMark. Its sequential transfer speeds were measured to be 208.8MB/s read and 183.1MB/s write. Both of these are almost as high as as some other USB flash drives.
In the random 512K block transfers, the Toshiba TransMemory Pro 64GB performed well in read activity (156.6MB/s). However, it was slower in write activity, scoring 24.37MB/s.
Both random read and write of smaller (4K) files was very slow, but don't forget that this is not an SSD.
As you see below in the screen shot of the the ATTO Disk benchmark, the drive's write and read speeds gradually increase as the benchmark performs file transfers ranging from 0.5 KB to 8192 KB. For instance, the write speed with small, 4K files was 35.84 MB/s, while reading was a bit faster at 37.88 MB/s.
The drive's speeds topped with 8MB transfers - 145.1MB/s for read and 205 MB/s for write. Notice that the write speed even reached the 210MB/s with 256/512KB transfers.
The Toshiba USB3.0 TransMemory-EX II 64GB drive is also compatible with Apple's computers. We plugged the drive into the USB 3.0 port of a MacBookPro 15 Retina (Middle 2014), which was running the OSX 10.10.2 OS.
Below you see the result of the Disk Speed Test by Blackmagicdesign. It is an easy to use tool that measures the performance of a disk performance for working with high quality video. The software write/read tests the disk using large blocks of data, and then displays the result. The read/write speeds for the Toshiba USB drive was 218.2 MB/s and 173.6MB/s, respectively.