I think everyone is entitled to their opinion as long as they dont trash the item up for sale. How is it that one can say "oh that's really cheap" but not "that's a little overpriced"?
I doubt that all sellers pay attention to FS threads on this board. So IMO I think it's appropriate for other members to say things like "this member sold you the same thing last week for X amount. your price is a lil bit much".