Ok, yeah that's what I meant. I had read that xenon retro-fits in normal reflector-type lenses can throw "stray light" in unwanted directions (particularly to opposing traffic) harsher than conventional halogens, since they weren't put into projector-type lenses which tend to focus the light straight ahead. But it sounds like you're not really having that problem which is a good thing.

If there are capacitors in either the ballasts or those black modules, then they'll hold a charge for a little while after power is turned off until they discharge. It's like a little battery downstream, probably to ensure they receive "smooth" power.

One more question. That kit is a 6000K (Kelvin) which in theory should be just slightly blue of white, where 5000K is generally considered to be close to pure white, like this:



I'm looking to get a kit as close as possible to pure white, but I've also read that kit ratings don't necessarily match up to the results depending on power output/ballast quality/etc. Does yours look like the 6000K above? If so, I'll know that the 5000K should cover my needs.

 

Mine look like the 6000k ones. I will say that they are very bright and 5000k should be plenty fine. As for the stray light it's noticeable on anything that is reflective which is mainly road signs.

Regarding the discharging of the ballasts, I see your point but I don't think that is the problem for two reasons. One the lights turn off at precisely the same moment and I would figure that if it took time for the ballasts to discharge they wouldn't always be at the same time. Two, when I contacted the supplier they said that the lights should turn off when the lights are turned off.