thing is a rst be it escort or fiesta is not a everyday car where as the zetec s is, as it has thing like power steering and all mod cons, the RST/FRST are more a enthusiasts car which is why they are covered under classic car insurance nowadays, and not telling your insurer about engine mods etc is asking for a one ticket to trouble as only a mug or a thug would risk other pedestrian/drivers safety with a illegally insured car