When I make a file transfer from HDD to pendrive(cheap sandisk USb2.0), Transfer speeds are extremely high (80-250MBps) intially and transfer indication stops(sometimes hangs) at end. It will usually become normal after sometime (It is taking same time that normally it takes in windows for complete transfer). Speeds are normal(18-22MBps) while transfering from pendrive to HDD. i have also tested using my another corsair pendrive and still the same.
laptopmodel : Asus X55C dualboot with windows 8.1