On my 2012 C250 CDI the 'flat' bonnet badge can be removed in a matter of seconds, and the raised star fitted in the hole in the bonnet. (videos available on YouTube) Whole job takes less than five mins, but as pointed out it isn't to everyone's taste. Word of warning, I bought a matte black 'genuine' version for around £20 - £30 on ebay, and it collapsed in my hands when trying to fit it! I have a chrome version that I paid almost double that for, but it is of a completely different build quality, so I guess it is actually a genuine one.
Have just been outside to get some photos. One showing poor quality of 'genuine' matte black raised star bought from ebay, one showing required part number (there are different sizes available), and one showing the hole in the bonnet. I hope this helps.