Yes its perfectly legal sensible and cost effective to replace the standard bulbs with better higher quality bulbs designed to be both legal but to give higher light output.

I've and others here have had both Philips (extreme) and Osram (nighbreaker versions) for many years in multiple cars, they cost anything from £17 to £25 for a pair of H4/H7 bulbs, to date only had one bulb has blown despite many comments on forums opver the years that they don't last long.

I would suggest you stick to either Osram or Philips for good quality and don't go for any multi coloured or LED replacements because most likely to fail the MOT and unless you pay serious money the beam patterns won't be right with some cheap LEDs.

Don't forget if the plastic outer headlight lenses are going cloudy as many do you can polish them crystal clear again and then seal them, sealing is most important because once you polish the plastic lenses they sun quickly clouds them again because you've taken off the anti UV layer...if this is an issue the various methods and products have been discussed quite recently here so a quick search will find the answers to this for you.

Just one thing Scot, you haven't got OE HID's or anything have you?, ie when you first turn on the lights they start dim and then brighten up rapidly as the ballasts behind the lights get going...these are a different kettle of fish altogether, i don't think you have them because they are generally good lights in tghe first place, but just double checking, your handbook should confirm the bulb reference but it might be a Merc part number in which case you maye have to whip a bulb out to confirm if you need H4 or H7.

If elekiedoc spots this thread he'll no doubt know the exact system your car has and the bulbs reqd.

Edited by gordonbennet on 30/01/2023 at 12:06