After having black for every previous iPhone, I got the gold 6 Plus. While I loved it for a few months, eventually the novelty wore off and I found myself disliking the look of the white bezels. For the 6s Plus, I'm going back to space grey.
Funny thing is, I have a silver iPad and I love that, but that also has a smart cover on it so usually when I'm using it, the screen is lit up. On the iPhone, a lot of the time the screen is black, but I have it near me and uncovered, so I'm seeing the black face and white bezels and it doesn't work for me.
Once I got my Apple Watch, space grey sport, I knew I needed to go back to black bezel phones. It looks like such a mismatch to have a black AW and a gold iPhone.