Do powerline adapters have better speeds than WIFI repeaters?

[neder]

I've noticed with my BT wifi disc repeater, I get half the speeds of my router, meant to be getting over 500mbps but am only getting around 180-200 mbps from the disc, probably because the walls in my house are very thick, despite it being quite a small house.

Will something like a 1200mbps tp-link work better?

[kelper]

What speed do you get if you connect a laptop to the router with an ethernet cable.  Use a Cat 6 or better.