We've been in dressing rooms that have sent us screaming out of the store and straight to the nearest Yellow Pages in search of a plastic surgeon. It's curious that the millions of dollars spent by retailers on marketing research has not led them to this simple shopping truth: If you look ugly in the mirror, you won't buy the stuff you're trying on. (Here's our fancy marketing tip: Tone down the operating-room lighting and give people more than six inches between themselves and the mirror. That'll be a million dollars, please.) Neiman Marcus must have highly paid consultants, because its ladies' dressing rooms are like lovely studio apartments, with lighting suitable for a cocktail party. There's plenty of room to stand way, way back and squint your eyes at your reflection, if you're so inclined. If those mirrors don't make you look good, then you know you'll fare far worse under your office's fluorescent lighting. Buy accordingly.