I love my R172 55, it's a brilliant car and I can't wait for my next drive. I have the 10 spoke gun metal alloys and they look great with a white car too. I love the Bengal Red interior, but wish I had carbon fibre highlights, the best part however is that V8.
Don't know about the 55 being the poor relation in the AMG line up, it's bonkers to have a 5.5 litre V8 in such a small car.....who would do it except AMG.
I'm sure you'll love it! By the way I'm considering having the wing badges removed they're the only bit of the car that looks chav.
RR