Tegra 4 reference tablets use SanDisk iNAND Extreme
 

It's well established that NVIDIA's Tegra 4 is at least reasonably quick. It's only quick when the storage isn't a bottleneck, however, which is why SanDisk has negotiated a repeat partnership as the official storage supplier for reference Tegra 4 tablets. Pop open one of the designs and you'll find either 16GB or 32GB of SanDisk's iNAND Extreme keeping pace with the quad-core processor. The reference deal may be more than just a publicity grab: it raises the chance that companies will use the speedier flash memory in their own Tegra 4 slates. Whether or not SanDisk makes it to shipping devices, the deal could lead to balanced tablet hardware that seldom leaves us waiting.

http://www.engadget.com/2013/02/26/t...inand-extreme/