The more I read about this thread, the more I feel compelled to get one. I really could use a new bag right now and feel the 256 is a good size. Although I feel a toss up between the beautiful tan or brown; slightly worried whether the tan would face the elements and retain its colour over time.
Just FYI - I bought the brown 258 for the same reason (to hide stains) and it does fade over time. In some ways, I think it ages much better than the tan. It has faded in areas and begun looking very nice. I seem to get more compliments on it as it has aged. It is still brown enough to hide dirt well but is getting a nice distressed look.