If you have an aftermarket headlight conversion. Your light will burn out faster if not the right wattage. Say for example your old lights take 9000's or something and your new headlights takes H3 or H1 those are fog lights not headlights. Plus somepeople touch the bulb with out even knowing it and their bulb dies quick, and then they use another bulb and don't touch it and it stays lite for many years.

OSRAM SYLVANIA Silverstars, Well woth my $40 bucks at "Advanced Auto Parts".

Silverstar and PIAA both put out 4000K but the color of the bulb on the PIAA bulbs Constricts more light from coming out and the color on the Silverstar will make a blue/Purple light and cuttoff line on the wall without lousing light output, I compared and the silverstar was much brighter.

I have them in an ebay projector headlamp (people in these forums say the ebay projectors are crap and to an extent they are) but all other lights could not make the purple/blue flicker, the silverstars did and are truely the look of HID with out the HID price, and the road is very noticeably bright now.