I've been using the same 9006 4003K HID kit in my LC for over 2 years now (30 months to be exact). When I got mine, they were "cheap" at $70 (same ones now are $35 online) and there have been times I've been flashed, but for the most part I don't. This is with driving on the freeways and suburbs in LA county. But for reliabilty, they are still going strong and no discoloring or fading has happend.... they're still bright white just as they were on day 1.
I didn't bother changing out the high beams since I never use them. The HIDs are very bright to where if I pull up behind somebody at a stoplight, I can see my headlights blinding them in their left rearview mirror through their back window. I know it's too bright too look at (when my wife drives the truck and I'm in front of her in my other car), but as long as it doesn't cause any problems for me I'll keep using them since it lights up the road great at night. I'm using bright, bigger 194 bulbs in the corners so that kind of offsets the HID brightness just a bit.
One more thing to add. I tinted my windshield with 50% tint (not dark at all, but enough to reject a lot of heat when parked outside in the sun), but I did notice it being a little harder to see at night, even with the HIDs. IMO, using 50% tint on the windshield and HID's is still better visibility than halogen 9006 bulbs and no tint, but you can see a difference. I've gotten used to it now so it doesn't effect my driving at night.
