kaval- Much as I simply *LOVE* high-quality single stage, and especially my two cars with (factory) single stage metallic paint, I'd absolutely go with b/c for a metallic.
SS metallic is a pretty fragile paint and you can't do *NEARLY* the amount/degree of correction on it that you can on b/c.
SS metallics look cool IMO, but they're not fun to live with. Gee, sorta like [insert smart-aleck analogy here

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