I have a pair of Alex's angel eyes from Alpine, and my angel eyes are perfect *knock on wood* i havent had any problems burning out or nothing. i know my friend who has an e90 M3 like me says that his LUX angels get really hot and then flicker and then turn off especially in traffic. where my HID angels stay strong all the time.
Advans is correct.
espeically about the color temp burning cooler.