On one hand, the FFXI method would address undercutting. It is blind bidding. Sellers don't know what other sellers are selling for. Buyers only have the buy history (which we already have). Some of the limitations are stacks. I suppose the WoW method of bidding for 50 items at a certain price would just give you the lowest 50? Seems like it would require some overhaul of the MB system. How does the MB figure out those 50 purchases if someone else is doing a purchase of any one of those 50 items.