I would get Space Gray simply became of the black face. I really dislike white face fronts on electronics and Apple seems to think that anything that isn't a shade of gray needs a white face. That blue is sharp. So sharp that I might have considered a blue Nano if it had a black face front.
I think my last black bezel/face was the iPhone 4? Had white since the iPhone 4S, 5, 5s, 6, and of course the iPod touches. I understand why people like or must have black, but it is true Apple has way more i-Device models with white instead of black fronts. White's definitely easier to find in a hurry!