my .02. id go with blue steel if it's truly in the grey family. I'm sitting here looking at my office carpet and it's made up of orange/light grey/dark grey squares and the dark grey are the only ones that don't show the dirt. I bet the darker grey will hold a more consistent color longer. black is nice but bet it'll even show dirt quicker than the darker greys.

that blue would be a tough box to check for me as it's a bold choice but it looks good in that boat.....