I had 'em. I pulled them out.
One issue is that the vast majority of conversions do not put proper caps in front of the plasma and oncomnig traffic is blinded, pure and simple. It isn't a matter of focus - the plasma balls are simply out there in front of that traffic. So whatever you buy SHOULD have metal caps over the front of the bulb if you want to play nice.
That 'fringe' that OCFJR mentions is MORE light that is blinding oncoming traffic becauise it simply isn't where it is supposed to be. And that IS a focus issue.
If your jusrisdiction does inspections, note that conversions are not legal. Period. You could wind up failing inspection if the person is on the ball. You can also be given a ticket for a mechanical violation is a police officer has it in for you. Then again, th same applies to exhaust conversions.
And, while quality HIDs last longer than halogens, note that the garbage coming out of China these days tends to fail pretty quickly - especially the ballasts and the painted blue bulb of the capsules that use those halogen high beams.
I do run proper HID driving lights, but they are Hellas and use German ballasts - they NEVER fail to fire and mine come on with the key, unlike those plug and play conversions - that alone says something. Mine have been running for almost 40K miles without issue and thay are on almost all the whole time that my bike is running, unlike my headlights, which are on high beam during daylight hours and low beam starting as duck.
Since I have a friend that owns a car customisation shop, I was told (and experienced) that the cheap Chinese conversion I tied (which was an HID low and Halogen high) suffered from arcover across the pins, leaving a carbon trail, which would have done in the ballast in fairly short order.
If, after everything you decide to go the route, note that you should buy 4200 degree bulbs . . . those look somewhat whiter than the 3400 degrees that a normal halogen bulb does, but not the bluish light that frankly provides less datail for the human eye because we aren't as sensitive there.
Yes, a 6000 degree HID will light things up farther than a halogen headlight, but that's because you have double the lumens - but your most efficient color temps are the 4200.
Lastly, note that the startup inrush current for HIDs is VERY high - on the order of about 15 amps. The bike's electrical system really isn't designed to carry this - and while I've yet to hear of a wiring, socket or relay failure due to a conversion, note that it IS a distinct possibility.
If someone wants a set of very low mileage (as in perhaps a week's use) mid-line Chinese conversions, C$125 takes it from my garage in Montreal.
Edit: I see that Pierre is on the thread . . . perhaps you'd like to try 'em?
