These will generally work if the outlets in question are on the same leg, or "phase", of the house's power. I don't really know what home wiring is like in the UK, but here in the States houses...

The spec provides for the possibility of interoperability between 1.0 and AV. From the HomePlug AV whitepaper (emphasis is mine): The AV PHY enables coexistence and interoperability with HomePlug 1.0...