The LED headlight thing is a constant discussion on car forums. This article is 8 months old, but someone just posted it yesterday in a forum I frequent and it is my first time seeing it. I found it interesting.
TL;DR, My summary of why LED bulbs in non LED headlight housings don’t work was overly simplistic according to this article, but it was essentially accurate. You can’t mimic the light from a halogen bulb with an LED bulb with current technology. People that attempt it are often blinding other drivers while also giving themselves poorer performance.
All that said, LEDs are bad for headlights (EDIT: as a bulb upgrade), but can be good on other parts of the car. I wouldn’t replace any interior lights with LEDs (because most interior LEDs are too bright compared to the specifically selected bulbs that the manufacturer put in). But when I had a very difficult to replace 3rd brake light bulb go out on my wife’s car for a second time, I replaced it with an LED in hopes that it will last a little longer this time. I am not looking forward to laying on my back in the trunk and trying to fish a tiny bulb into a weirdly placed socket through a small metal hole that can fit only two fingers ever again. I might sell the car if that bulb goes out one more time.
) .
