The original shades of gray used in LEGO sets were phased out in the mid-2000s in favor of bluish grays, making the choice of elements in the original grays limited. However, this limitation can lead to creative uses of those parts, such as in this NATO “Devil” Main Battle Tank built by Carter Baldwin. The angled armor plating on the turret stands out as my favorite detail here, but the whole build has a great flow to it.