There are some seriously powerful light on the market that enable you to see several kilometres up the road. The thing is, not everyone needs this level of brightness and you can spend a lot of money on something that is above and beyond how you use your 4WD.
Driving lights are generally considered to be spot or flood beam. That is, they shoot a lot of light to a narrow spot for a greater distance ahead, or they spread it out wide, but not as far. If you are travelling into the night at high speed, then seeing a long way down the road is a good idea. However, if slower, windy roads are your undertaking then a wider spread with less distance is more suitable.
You also need to consider how frequently you will be using your lights and align that with the type of travel we discussed in the previous paragraph. Spending a significant chunk of money on driving lights is unnecessary if you only use them once in a blue moon.
A lot of spotlights come split, with one as a spot beam and one as a flood. Light bars are also being made with part split and spot arrangements to give you the best compromise. The alternative is to fit two styles of lights and have the best of both worlds.
