Lumens simply measures the total quantity of light emitted at the source. It does not take into account the ability of the light to direct that light into a usable pattern, which is a critical function of a driving light. Lux, on the other hand, measures the total distance travelled by that light beam, which is a function of the precision with which the reflectors have been designed and engineered. It is a much better measure of the quality of a light.

Driving lights will generally give you a greater forward distance, whereas light bars will give more spread to the sides of the road. As technology improves we are starting to see more crossover between the two i.e. driving lights with improving flood capability and light bars with increasing forward distance, but the difference in shape will mean that each type of light will always have an inherent advantage over the other in one area.

It is worth remembering that LED chips contain many microscopic parts, and the manufacturing process is very complex.

Firstly and most importantly, higher-quality chips will last much longer on average compared to those of lesser quality. Given the difficulty in replacing an LED chip compared to say an HID bulb, longevity is of paramount importance. There is nothing worse than having an LED spotlight on the front of your vehicle with a few dead chips!

Secondly, high-quality LED chips will be much more consistent in colour temperature, which means the appearance of the LED driving light will be much more uniform. LED spot lights using high-quality LEDs will have a better Colour Rendering Index (CRI), which is a measure of the accuracy with which the light reveals colours to the human eye.