Some in depth info on HIDs can bee seen at

Daniel Stern Lighting Consultancy and Supply

I also note they still have Cibies that I first fitted in 1970 ish.

 

That article seems a bit lengthy and far-fetched to me.

I completely agree that the use of HIDs in standard halogen assemblies is both dangerous and inconsiderate to other drivers, but I see no problem with using them in cars like the X-Type which have projector headlamp assemblies already. In fact, I would tell anyone who asked me not to do the conversion unless they had a projector style headlight or were planning to replace their headlights with projector-style replacements.

On the point of electromagnetic interference, I haven't heard of anyone encountering this problem but I can see it being an issue with perhaps some of the very cheaply made kits. However, it seems to me that if this were an issue the individual operating the vehicle would realize so as soon as they first flipped the switch to turn the lights on after installing them. The argument could be made that any poorly made electronic device would be able to interfere with a car's systems, but that possibility would likely be negated by simply not buying from a Chinese distributor on eBay who can't speak English.

The bottom line here is that our cars are perfectly capable of handling HID bulbs in a way that makes them look stock. If I were you, I'd get a kit with good reviews and not worry about the things mentioned in that article