Only if you purchase the wrong ones...
Mine, ok, may be a grey area as there is no self levelling or washer jets but they are specially designed for use with a reflector style headlamp unit and so do not cause glare. try carmodshop for a set
Someone has been telling you porkies. You can't design a discharge bulb for an incandescent filament reflector and lense. The geometry is different - unless the manufacturer has disproven wave particle duality and thrown the known laws of physics in the bin... Methinks not...
Loads of misinformation in the market on this topic.
Please refer to this link
http://www.dft.gov.uk/pgr/roadsafety/drs/hidheadlamps
Now i'm not saying you shouldn't fit these kits; it's a personal choice as to whether you are happy to take the risks, but people should also be aware of the technical issues surrounding the installation of aftermarket HIDs
i.e.
An HID bulb in a halogen lighting unit will not focus the light correctly due to the different geometry of the arc
The human eye is less sensitive to the higher light temperatures produced by HID bulbs, so while more light may be produced, the advantage is largely negated.
A lot of aftermarket bulbs are advertised as 'white' with temperatures of 6000K and above to provide greater brilliance, contrast or some other sales pap. In reality the most efficient colour temperature for HID bulbs is 4300-4500K, hence why ALL OE manufacturers use this range. Also (see point above) they produce a higher percentage of more 'visible' light.
In summary, there's nothing to stop you fitting HIDs as long as you're aware of what's involved, and you understand there are good reasons why car makers are required to fit HID specific optics and levelling systems.
If you want some funky light and aren't bothered too much about seeing where you're going, change the bulbs for HID.
If you want the best lighting, either fit the best halogen bulbs (Osram / Philips +50) or change the entire headlight unit.
Not a rant, just information.
Happy motoring
James