Male in a blue collar job chiming in - I have an aversion to the space grey aluminum finish due to experience with it on the MacBook - it doesn't hold up as well with age and it shows grime too easily.
I started off with an aluminum/white 38mm Nike+ which I wore pretty much all the time, but the band felt out of place to me in more formal settings. So, after a month or so I supplemented it with a regular stainless steel + Milanese loop. Honestly though, buying another band was all that would have been necessary but I found the steel model for a price I couldn't pass up on.