those are a thousand times better than WiFi, but a real ethernet cable is many times better than PowerLine Networking...
You dont have finished walls, dont worry about those gadgets until its too late and you realize you shoulda ran more wires.
if I were building a house today from scratch, every TV location would have 2 ethernet cables, every room would have a phone mount on the wall with an ethernet cable for a VoIP phone, every corner and entry of the house would have an ethernet cable for cameras, and each of the kids rooms would have an ethernet cable to the celing for a nanycam.
and thats just for starters.