The SanDisk Extreme microSDXC UHS-I memory card series are said to be the perfect companion for your smartphone, tablet and cameras. With read speeds of up to 80MB/s and write speeds of up to 50 MB/s the 64GB card also just happens to be the fastest 64GB microSDXC card available. Read on to see how this memory card performs when we test it out on a PC with a USB 3.0 card reader and on our Samsung Galaxy S4 smartphone!
