Already the first stick was only briefly, was no longer detected after 2 days. But change went quickly thanks to Amazon. The 2nd was then quite well so far (1/2 year), and the USB 3.0 port (with rates of around 80-90MB / sec., According h2testw). Now he turns out again and again. Copies run initially fast (about 60MB / sec.), After a few seconds. Decreases the value constant but decreases to USB 2.0 values. Copies via USB 3.0 are even stop in the middle, allegedly recognized no storage medium. Even then eject does not work, is allegedly used. When connected to USB 2.0 but transmits all data rates to the 30MB / sec., But I do not buy expensive USB 3.0 flash drive. I have now lost faith and wonder about the many 5 star.