Hi Gilbert,
I only have plated side vehicles, and they all have dark grey roofs. As far as I know, the wooden bodied ones all have white roofs, so this is a departure for Hornby.
I agree, it means the paint job for the roofs if they are to look realistic, certainly for the ECML formations..
I have one of the old,old,old ones with a silver roof. It is lost somewhere in the "underworld" beneath the layout !!!
Stuart