The only regret I have about my Model S is getting the tan leather. It looks great but it is really a light shade and will not hide even a minor smudge. Are there any scotch guard equivalent products for leather interiors? I read the thread on leather care and I purchased the products recommended by Artsci, but these seem mainly for cleaning after a stain. The alantra side bolsters and headliner also seem to pose unique cleaning issues. Thoughts?