After reading all the informative posts here, I'm closer to recommending a solution to enhance the low projector headlights of a friend's Audi A6 2000.

I was bent on recommending HID bulbs (to replace the stock halogens) which I gather will work on the A6 projector lamps. Kaya lang sobrang mahal pala. Yung McCullough, P18K yung promo price sa Motorshow. Yung xenon naman, P36K po. It's a lot of money for city driving.

Since hindi po importante yung porma, I reckon sticking to a halogen replacement bulb is still the best bang for the buck, in a manner of speaking.
I'm inclined towards the Philips Diamond Vision, since ito lang po ang alam ko.

I'd appreciate your recommendation on other reliable halogen replacements for projector headlights?

Maraming Salamat po.