i got the tp link av500 from maplin and i plugged it in an extension cable the host and the reciever in another extension cable and i did a speed test and i got 6Mbps, i then tried to plug my reciever in a wall plug and it went up to 11Mbps and last of all i plugged in my host in a wall socket and finally i got 20Mbps, so it does decrease performance if plugged in extension cable and i have to say so far so good im liking it but i have to say my wireless is the same performance so i dont see any point