Well then we probably stand out :p....inside and outside in anthracite
Add me to the outliers as well. I also have anthracite (RAL7016) inside and outside.
But I'm more of a Bauhaus style furnishing type with designer furniture. I think you have to consider how the room will be furnished afterwards.
Also, at least for me, anthracite looks better with higher windows and corresponding room height.
White-white was somehow too boring for me. I had considered anthracite outside and white inside for a while, but then consciously decided on the contrast inside.
But basically, it's really a matter of personal taste.