well by the looks of things, its only the main dealers that sell the proper replacements for the xenons.
apparently the cheaper headlights i'd been quoted for were for the standard halogen without fog. Also the proper replacement comes with the starter and some other clever stuff hence the price, either way this should turn up at the dealers tomorrow, so hope to be back on the road Thursday lunch time.
Also i was informed by the bloke on the part desk who was quite helpful that the lamp protectors are compatible with the MK4 xenons however the MK5 protectors can't be used with the MK5's bi-xenons