I have a friend of mine that for some unknown reason HATES DRLs. I have them on my Silverado and give them zero thought until he brings them up. He rants on how bulb life is reduced and how it impacts his gas mileage. Seriously, does anyone think that when the DRLs are on that it significantly impacts their fuel economy. I had a 2008 Silverado and now a 2013 Silverado and I have never even needed to touch the headlight switch. The DRLs are on during the day and the headlights switch on when it gets dark. As far as bulb life, I had to replace one bulb in the 4 years I owned the 2008 Silverado. My old 2002 Explorer Sport Trac did not have DRLs and had manula headlamps and I had to replace both headlights twice in that vehicle, and to boot the Sport Trac with a V6 engine got worse fuel economy with cr@ppier power than either of my Silverados.