Problem with the Gigabyte is that it puts a whack on your PCI-E lanes somewhat crippling your GFX options if you wanna maintain full USB thruput. What Gigabyte does is essentially sacrifice half of its peak bandwidth to enable 5.0 Gb transfers to the USB 3.0 and SATA 6.0 Gb/s controllers, while those with two cards must live with 2.5 Gb/s bandwidth limits on USB 3.0 and SATA 6.0 Gb/s controllers.
So if you have multiple GFX cards....
w/ Asus you get 5.0 GB/s transfers on USB 3 and SATA III
w/ Gigabyte you get 2.5 GB/s transfers on USB 3 and SATA III
Of course you need something that can pump that for it to matter.