On HD Tach we could measure two parameters: the average read speed, listed in megabytes per second (the higher, the better), and access time, listed in milliseconds (the lower, the better).

Rally USB drive from OCZ was the fastest device in our roundup. On HD Tach 3 it was 39.06% faster than Corsair Flash Voyager, 156.73% faster than Kingston DataTraveler 2.0 and 221.69% faster than MSI Mega Flash. Really amazing. Corsair Flash Voyager was 84.62% faster than Kingston DataTraveler 2.0 and 131.33% faster than MSI Mega Flash.

Using these results, we can make a rough calculation of the time you would spend transferring all data stored in the USB drive to your computer, assuming that it is completely full. The MSI model achieved a better time because its capacity is only of 128 MB. If it were a 512 MB part, its transfer time would be 61.68 seconds.

Product	Transfer Speed	Transfer Time
OCZ Rally 512 MB	26.7 MB/s	19.17 seconds
Corsair Flash Voyager 512 MB	19.2 MB/s	26.66 seconds
Kingston DataTraveler 2.0 512 MB	10.4 MB/s	49.23 seconds
MSI Mega Flash 128 MB	8.3 MB/s	15.42 seconds

Access time measures the time the time the computer spends accessing the device before starting transferring data. The lower this value, the better, i.e. the fastest the device is. Under this test Kingston DataTraveler 2.0 achieved the best result, 0.5 ms, just 0.1 ms ahead of OCZ Rally. MSI Mega Flash achieved 1.1 ms while Corsair Flash Voyager achieved a very high access time, 18.3 ms, being the worst product in this parameter.