CrystalDiskMark is a synthetic benchmark that tests both sequential and random small and mid-sized file transfers. It provides a quick look at best and worst case scenarios with regard to drive performance, best case being larger sequential transfers and worse case being small, random transfers.
CrystalDiskMark Benchmarks
Synthetic File Transfer Tests
In the sequential transfer test, it was the WD My Passport Ultra leading the way by the smallest of margins, although the Toshiba drive once again trailed the pack. In fact, the WD drive handily beat the LaCie and Toshiba in each of the CrystalDiskMark tests with its write speeds; there was less of a delta between the three competitors' read speeds.
It's also worth noting that the Toshiba drive performed better than the LaCie in the 4K and 4K QD32 transfer tests.