Recently purchased used 2003 A6 Avant and am extremely pleased. However, lost passenger side low beam headlamp and purchased Philips D2S 85122 bulb on eBay. All seems to check out OK, but I notice that the new bulb is not as white/crisp as the replaced bulb. The replaced bulb was Osram Xenarc D2S 66040. Done some further research and both bulbs should burn at 4300K so wondering if I'm just experiencing this "color shift" that might occur. Will my new bulb eventually burn as bright/crisp as the existing? Should there be a noticeable difference between the two bulbs right now?