I actually purchased the medium brown color which blends well with my area rug close by.  So far, I'm very pleased with my purchase.  It's in a low traffic area, but one which will receive the moisture from a rainy event which hasn't happened as yet.  The mat is easy to vacuum and the grippers on the reverse side keep it in place nicely.  I wouldn't hesitate to purchase for either the interior or exterior, as long as it's a covered area.