They do work with HomePlugs 1.0 spec but they only do 80mbps through the network ports and 200mbps through the powerline. So no good if you have 100mbps cable and want to send the internet though them.
Seem that the code is no longer valid. PC World have dropped the price to £24.99.
I got mine this morning and so far am not really impressed. Works fine in the same room but I've got one in the living room and one in the conservatory and the "performance" light is constantly red and the signal keeps dropping out. It also did the same when I put the second one upstairs. The range is supposed to be 500 square metres but I get a better signal from the virgin superhub and that saying a lot.