Thanks, George!
Yes, I was looking at videos and only one was flickering (it was an OLD car)... The rest had this cool quick start-up, then it took a couple seconds for the light to come to full brightness. It's actually pretty cool! I was just curious if it happened to all HID lights - even OEM ones.
My previous car, an ML350, did not have HID lights, but my mom's Lexus does - I think I've sort of noticed that happening, but with hers, I see the lights leveling. Then again, I don't her car all the time as she is in MA!
Thanks for all your great advice and answering my crazy questions!
-David