Metropolis vs Thunder Gray

Both from Sherwin-Williams's palette. Both sit in the grey family, which is useful context if you're narrowing within a single hue direction. They have nearly identical light reflectance values (8 vs 9), so they'll read as similarly Dark in most lighting conditions. Both lean neutral, so they'll behave similarly in mixed or changing light conditions. The ΔE 4.3 gap is real but not dramatic — close enough to use together, distinct enough to matter as a choice. Below, 5 simulated room previews show how each color reads at scale — real-room photos will be added as they become available.