Nowadays the users prefer taking high resolution pictures, full HD or 4K video and tremendous personal data, the first thing they care with the storage partner is the speed. Therefore, the orders for USB 3.0 flash drive get increasing sharply. Although there is no specific capacity range for USB 2.0 and USB 3.0, flash drive manufacturers will adopt 64GB or above for USB 3.0 due to the high transferring speed. The max writing speed for USB 3.0 on sale is around 300MB/s, this will never happen to USB 2.0.
Speed is the most obvious advantage for USB 3.0. Besides it, the stability of USB 3.0 is much better than 2.0. Why does it happen? As if one memory stick has good performance on speed, the flash it applied must be good die. These factors guarantee the higher quality and higher cost of USB 3.0.
USB 3.0 flash drives are backward compatible with USB 2.0 port; the unexpected part is the speed. As the performance of one USB drive is fully relied on the connecting port, if you read USB 3.0 in USB 2.0 port, the speed will be definitely in 2.0 ranges.