Flash (thumb) drives and SD cards have become increasingly popular for dagta/program storage and transfer because of their small size, high data capacity, and immunity to magnetic fields typical of airport scanners.
I just came across a bench marking program that may be of interest to the group for these devices. You can download it for free at
Some takeaways from the few benchmarks I ran:
There is a difference in the read/write speed between brands. The one new micro flash drives I checked was slower than the full size drives.
You can see the difference between class 4 and class 10 SD cards. For data transfer/storage most likely no practical difference. If you are using a SD card or flash drive as a "ReadyBoost" drive you may see a difference.
The older flash drives in addition to having less capacity are also slower. Again, this may or may not be of significance depend what you are using them for and the amount of data you are dealing with.
Still amazes me that you can get 128GB of data into a SD flash card smaller than a postage stamp. The micro sd cards are even tinier.
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