I've had experiences of buying an 16gb memory card to discover it can not take more than 250mb worth of files or that its really a "cloned" 2Gb SD card. I guess that I have a fake memory card, because the class speed under performing and sometime losing my files, photos and experiencing data corruption from flash memory chips. yep it's sucks. until I changed my memory card everything is back to normal. btw, to check if your Micro SD drive has the capacity and speed stated, "H2testw" is a simple tool that is distributed for free from your laptop.
@Prasetyo link is not working