[quote=AK]”Lighting up” in daytime has a small but measurable effect on fuel economy, and reduces the life span of your headlight bulbs … which can lead to them crapping out at night when you actually need them.
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LED lighting usually takes a long long time before they crap out. Also, a lot of the auxilary lights use a different bulb from the main driving bulb. Lastly, with the exception of Xenon discharge bulbs, halogen bulbs are pretty cheap to change $5-10.