Storage Tests
We're using the latest SanDisk Extreme Pro Portable V2 external drive to test USB performance. It offers up to 2,000MB/s read and writes, but neither board has the requisite 3.2 Gen 2x2 port for maximum oomph.
What we can say is that ASRock's total chipset implementation is at least as good as a more expensive Asus. No qualms on this front.