I'd have to agree with Dave - if the sporran is monochrome, the sporran strap/belt should be the same color as the sporran. If the sporran is 2-tone, then match the sporran belt with the predominate color.

I understand it's a matter of perspective, but buying 2 sporran belts seems like a minor expenditure compared with many kilt accessories. Go ahead, splurge - you're worth it!
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