It's a feature I can take or leave. It was kind of annoying on the Beretta on bright sunny days, the lights would come on if you went down a section of road with a heavy tree canopy, dimming the dash indicators (ie-radio/clock) then go back to DRLs when you came out into the sun. I'm sure it's more sophisticated today. My wife's car has auto headlights, but I don't drive it enough to know how it deals with situations like that.
How do states that have headlights on when raining laws deal with DRLs? Do they consider them "headlights", and how do they tell the difference if it's the same lamps, just different intensities?