stream

Xenons are a must. I've had them on my last 6 cars, and they really make a difference. And the E60 xenons are bi-xenon (both low and high beams) and (at least in the US) are adaptive, meaning they turn left or right as you go into curves. I recently borrowed a friend's car to move a few items, and driving at night without xenons was was like driving with half the light. Xenons are so much brighter, and cast the light much farther ahead of the car.

stream

No such thing as xenon fog lights, but you can get fog bulbs that match the xenon cloor very well:
http://forums.e60.net/index.php?showtopic=7232&st=0

my530i

I don't have Xenon and I regret not to have it. It's a must next time.

Incadescent bulb performance will degrade over time and you need to replace it new one every year or two to make headlight bright again. It's not the case for Xenon light.

skaffa

NO it's not every one or two years, but every about five years.

Skaffa

BMW530

Get them. Must have.

Ed520

you got to get them....forget abt adaptive but you got to get bi-xenon

realtyman

They are a must have IMO! I still can't see how the Xenon Hi-Beams are legal in the US.

mflauer

You'll kick yourself if you don't get them. Definitely a must.

goyk

Here's how xenon's work (from howstuffowrks.com):

Blue-ish headlights are not very common yet, but they are likely to become the norm because they produce more light than normal headlights while at the same time using less power. This combination is hard to beat!
There are several different articles having to do with light here at How Stuff Works:

Halogen lights
Gas camping lanterns (the kind with mantles)
Lasers
Fluorescent lights
Electroluminescent panels
All of these technologies excite atoms so that they produce photons. In the case of halogen bulbs and gas lanterns, heat is doing the exciting. In other technologies it is various forms of electricity or light that create the excitement.
Most cars currently use halogen bulbs in their headlights. The new blue-ish headlights are using a different technology called High Intensity Discharge (HID). We normally see HID lamps in the form of mercury vapor and sodium vapor lights used as street lamps and as outdoor lighting for stadiums. These lamps are popular because they are efficient. In the case of sodium vapor, they are twice as efficient as normal fluorescent bulbs.

Mercury and sodium vapor lamps produce light using a technique similar to that used in fluorescent lamps. In fluorescent lamps a low-pressure mercury vapor produces lots of ultraviolet light that excites a phosphor coating the tube. In the case of mercury vapor lamps, it is a high-pressure gas, the distance between the electrodes is very short and the light is produced directly without the need for the phosphor.

In the case of HID headlights, the same high-pressure technology is used. The lamp is similar to a mercury vapor lamp. However, designers of the headlights had to solve one problem with normal mercury vapor lamps -- the fact that they have long start-up times. Xenon helps solve the start-up problem, as does a special controller. All of these tricks mean that these headlights are expensive now, but mass production should bring the cost down eventually.

ricky

Absolutly worth it!
I can suggest Adaptive Headlights too another essential option.