Do those ethernet plugs that you put into walls bad?

[John55]

I am trying to use ethernet but I am on the floor right above the router and my mother does not want a cord drilled into the wall/up against the wall. So I found these online: https://www.dell.com/en-us/work/shop/tp-link-av1000-gigabit-powerline-starter-kit-bridge-wall-pluggable/apd/a9823883/networking?gacd=9646510-1025-5761040-0-0&dgc=st&gclid=CjwKCAjwp-X0BRAFEiwAheRuiwz-FBdGJbQcCKSYJhLt3cGrcT6n_Z_LM66H9PJfe4kIw4BEgobxAhoCefYQAvD_BwE&gclsrc=aw.ds

They are these things that you plug into the outlet and then use ethernet cables. Will these cause issues like lag spikes and high latency? Also, what is a good size cable that won't diminish the signal cause people told me that too much of a length will drop the signal. 

[The_russian]

Those are very hit or miss, it depends on how your electricity is setup and the quality of the electrical wires. If you have an older house, these may not work properly or will have limited bandwidth. I would look into other possible options and leave this as a last resort.