I just got a new A6. My 528 HAS factory Xenons. I wanted to upgrade my bulbs. Saw his site, asked for information. I received a canned message. I did research bulbs from about a dozen internet sites. I happened to go to my local autoparts store and purchased Wagner H1 bulb at 100w and put in the A6. It was pretty bright. To be honest, it provided almost as much light as the Xenons on my 528, just not as blue as the color temp is about 1200-1400 less. I bought Optilux Xenon Whites from an internet source. Believe it or not, these are by Hella and look darn similar to Jimmy's. They were not as bright as the Wagner. I am returning the Hella bulbs, blue tinge or not. They are not as satisfactory. At $9 a pop for a really bright H1, this is a good deal. Wonder if any other people have looked into this trade off. Jimmy bulbs seem darned expensive to me, regardless of light output.