I work in the head office of a Bank and shoes other than black are uncommon and, amongst middle and senior managers very, very uncommon. Which is not, in itself, a reason not to wear them. Square-toed, poorly maintained black shoes are pretty common, but they don't stand out because they are black and 99% of men wear black shoes to the office. One needs just to make a judgment about whether one wants to stand out a little, or not. Dark brown and burgundy will stand out, but will still, in my view, present as professional - provided everything else is okay. Cigar is on the border - but I wear it with a mid-grey suit in the warmer months. Tan is definately out.