I have used many Sandisk Pendrives.These are not upto the mark for their low-grade performances.Copying, transferring files is very slow than any other pendrive.The pendrives of Sandisk brand which we use nowadays is fake and not genuine.They can be easily identified by their performance.The outer surface quality is also very poor.The packaging is not good and proper.The performance is worst in case of capacity more than 16GB.