Looks like a really easy DIY but since I am totally mechanically inept and work at a BMW dealer, I had one of my mechanics do it for me. It took him all of about 10 minutes and it works flawlessly. Not sure of the brightness because I only saw it during daylight but I'm sure that it's more then enough. I think that this is most helpful when being tailgated, driving in front of someone who has their high beams on or in fog. Otherwise, it will remain off. Much thanks to the OP for the excellent suggestion.
2011 M3 Convertible, Alpine White/Black Novillo Leather
2008 550i Sport, Platinum Gray/Natural Brown (retired)
2006 550i Silver Gray/Black (retired)
2002 M3 Convertible Titanium Silver/Black(retired)
1998 328i Convertible Arctic Silver/Gray(retired)