The appearance is a little cheap. AC side flows, I've done extensive testing at Work and its maximum lies around 440Mbps for a displayed modulation ~ 585Mbps average (650 max). This is far from a theoretical 866.5 Mbps 802.11ac transmitter 2x2. For neophytes, 440Mbps = 55Mb / s (the USB3 manages 10 times). After everything also depends on the embedded controller to the key and the USB3 port of the PC.
However, for that price, it's worth it, provided you have a wifi AP managing 802.11ac with at least 2 antennas :)
