I bought these bulbs with high expectations, according to the motto who must expect to spend a lot a lot of money. I am not very satisfied with these bulbs. After only a few months (perhaps the that they are not blown) they lose enormously in luminosity and ultra white becomes ultra yellow. They also dazzle oncoming traffic. Then I'm going every few days alerted with headlamp flasher (I put the headlight range control to minimum).
The bulbs are now six months old and I expect really a daily basis that the first bulb gives up the ghost. Next, I'll probably try it but with Osram ...
