Consumer Reports is beginning to test headlights on new cars just like they test other performance parameters. Lets see if this link works!

Interesting points they made are the best and the worst headlights may be either HIDs or halogens, it doesn't matter as much as the design. So BMW may have dynamite headlights, both their halogens and HIDs, but it doesn't follow that all HIDs are therefore better, because CR shows that Audi's HIDs suck.

As for converting the Volvo halogen headlights to HIDs: "Halogen-bulb reflectors aren’t designed to properly direct an HID bulb’s greater light output," says Larry Rice, a senior optical engineer at Guide Corp., a major lighting supplier for new vehicles. Such kits can create glare--one reason why HID bulbs that have a halogen-style base violate federal standards."

As David has extensively researched and I can confirm, the E-code lenses make a world of difference. I have the "Brand X" E-codes which are a cheaper than the Volvo (Hella) brand, and they're still much better and brighter.

The Haynes manual I think gives some hints about aiming the Volvo headlights. I use a combination of the bubble levels on the lights and chalk marks on a wall; the odds of my dealer getting them aimed correctly are somewhere between zero and a negative number.

-Punxsutawney Phil