I'm purchasing a new iMac and am worried about the wired keyboard. I am worried that the USB 2 interface will slow down the USB bridge. I have multiple USB 3 hard drives that I need to run at USB 3 speeds. From my understanding, the USB port speed is dependent on the 1st device the computer sees as apple states in their FAQ: Thus, if I have both my USB 3 hard drives and my USB 2 keyboard plugged in, is there any possibility that the drives will actually run at USB 2 speed? Anyone have any experience or answers to this question?