It's all a bit grey, but the MoT rules are not as tight as the Type Approval requirements. You 'can' get away with decent quality aftermarket HID conversions, provided that the units do not produce too much dangerous glare, in the view of the MoT Tester. I have had them on my Renaultsport Spider for years without issue.
They' look very wrong in my opinion on an M3W though.....
