Well I have Xenon in my 300E. The best priced kits are the ones on ebay. They are OEM kits with Hella ballasts and Philips D2S bulbs. The Hella ballasts are more durable than any other ballast I have seen. The Philips D2S (#85122) bulb is very bright white with a tiny tiny hint of blue. That bulb and ballast combo is the best I have seen. I have that combo in my 300E. Installation is not hard at all. Stay away from those boxed "HID plug and play kits" that are on ebay. They use poor quality bulbs and ballasts, you will be sorry if you buy one of those.
Stay away from those "Bi-Xenon" boxed kits also. That "BI-Xenon crap is nothing but the cheap japanese made bulb and a movable glare shield. It gives the effect of bi-xenon, but the high beam does not travel any farther than the low beam. The moveable glare shield just adds more glare to the light and gives it the effect of being brighter. Since a xenon bulb has no filament, the only effective way to achieve true bi-xenon is by having a leveling motor in a projector housing that quickly raises and lowers the entire projector beam. It in turn moves the beam pattern higher. Those kits are a knock off! I feel sorry for the suckers that purchase those kits.
1987 mercedes 300E
1995 e320 conversion(hated the 300e grill)
Monochromatic Paint (Custom Blue)
Flat Badged (front)
custom "carbon fiber" console
18 inch HP EVO rims
Sold! Now I drive a Monte Carlo SS