So I've an express in another room I set up to extend my extreme wirelessly. My ISP plan is 300mbps.

However in the room with the express, for some reason is not catching the signal from extreme well. i'm getting ranges from 0.4mbps to 8 mbps.

I am going to try a powerline adapter from airport extreme > Powerline input >Powerline output > express.

I'm going to test this out soon and if it does work, my main question would be this.

Q. Because i've 300mbps,if i know the powerline is doing it's job well and it feeds the express with >100mbps into the WAN ethernet, the wifi output of the express or the ethernet LAN out will still be limited to 100mbps theoratically since the WAN only accepts 100mbps. am I right to say that?

Q. Now could I add a gigabit switch, such that powerline output > Gb Switch > express.
So that yes the express will still wirelessly output at limit of 100 mbps, but I could connect my Mac via ethernet to the switch and enjoy >100mbps cos it's via the gigabit switch. This will serve the purposes of occasional usage in the room by the wife, but for me who prefers higher sustained performance, i get improved speeds direct from the ethernet switch..

Thanks for any help! Kinda noob at all this.