Earlier today I installed the winter tires (mounted on alloys) on a friend's 2012 Mercedes C300. It was interesting to see that this car uses bolts into threaded holes in the hubs to hold the wheels on, rather than the much more common studs and lug nuts. I saw this on a few Mazdas back in the '70s, but had not seen it since. It makes installing the wheels a bit of a challenge. Is this standard for Mercedes? Any other manufacturers? What are the advantages?