I saw a slate grey cab with natural grey interior and it looked beautiful. Natural Grey is a gorgeous interior which you don't see much because (along with natural leather brown) it costs more than all other full leather interiors. To me, natural grey is more handsome than straight black and easier on the eye. Other high end cars have similar-toned interiors which they may call "anthracite" or something like that, not straight black, but more like charcoal. The carpets on the natural grey interior are especially nice. A warm, softer tone than black.