I have a 1GB internet line. When I test the speed using the virgin WiFi and stand near the virgin router i get about 980Mb/s (expected).  If I connect via Ethernet cable to laptop to the Virgin router i get the same speed.  The speed remains the same when I turn off the WiFi from the virgin router and just test via Ethernet = 980MB/s

In my case, I cannot get more than 600MB/s out of this device no matter the connection options (WiFi or direct by cable Ethernet).  I bought the Deco X60 because I was guaranteed faster than 1Gb/s speed.   I am getting 1/10th of the speed expected.

This seems to be a problem that is reported often in forums - please someone at TP-Link respond.