i have had the dealer install spots on my car, but the only problem with them is that they shine in a pinspot way. This, if you have 4 of them is fantastic, but with only 2 i find that it is not sufficient.
The best thing to do is go to PIAA online,
www.piaa.co.uk and then get a set of driving beam lamps. They look exactly like the mini ones, but to be honest. Come with better bulbs, they also beam much wider than the mini ones. Fitting can be tricky but any car electrical person will fit them for cheap!
BMW charged me £375 for fitting, when i wanted more spots, they said it would cost another £375, so i left it!!