Well, the only thing makes it special is the weight, which most people who use a shield won't care about and they'll just buy a regular fourth tier off Mudd for half what I offered, which is why your auction has been open for a week with no bidders. So if you have a minimum bid in mind for stuff it'd save everyone some time if you'd say so up front.
That being said, I could go to 40 bags because I -do- care about the weight. I don't think I care more than 40 bags worth, though.