I have to say, I agree w/ Avanti/Pete about the ambivalence and not being sure why. I never got too fired-up over that feature, though I've accepted such a detail if it were present on a portal I bought commercially. I just don't add the feature, for some reason.
Frank
P.S. Doesn't that girder-bridge, visible toward the bottom of the Harper's Ferry portal photo, look great in its real-life weathering!