I assume that this behavior is in preparation for eventual Wi-Fi Alliance certification, since the trade group requires "good-neighbor" behavior of this type, though the Wi-Fi Alliance has not yet implemented a certification program for 802.11ac routers. In my opinion, the router was unnecessarily deferential. My home sits a on a 10-acre lot, and my neighbors' routers are far away. Usually, my network client adapters don't even indicate that the neighboring routers are there at all.

On my 2.4GHz 802.11n benchmark tests, the RT-AC66U performed slightly below the average marks for all five 802.11ac routers, especially at close range (in the bedroom and kitchen tests).

When the distance between the router and the client was greatest, however, the RT-AC66U bested the rest of the field, with the exception of its reference-point cousin, the RT-N66U. In the test charted below, the client and the router were 75 feet apart.

The RT-AC66U's four-port gigabit ethernet switch performed as expected, delivering TCP throughput of 943 mbps.