Posh is hot. Whether it's leather bags, fine watches, or high-end clothing, consumers have shown an ongoing willingness to shell out cash for the finer things of life. With the purse strings of the well-to-do (and those who want to live like the well-to-do) a bit looser, shares of companies such as Coach (NYSE:COH), Nordstrom (NYSE:JWN), Movado (NYSE:MOV), and Neiman Marcus (NYSE:NMGa) have all managed to outpace the overall market.

Despite this robust environment, the company arguably most associated with luxury items in America, Tiffany (NYSE:TIF), has languished. Pressured by disappointing sales in Japan (a major market for the company), rising costs, and high valuation, the stock has underperformed the S&P by more than 30% over the past year.

Tiffany's fourth-quarter results aren't likely to have investors stampeding to buy more shares any time soon. Though consolidated sales were up 11%, Japan remains very weak, and earnings per share (after removing certain gains and charges) were up less than 10%. In an environment when most high-end retailers are seeing considerable operating leverage (and posting greater profit growth than revenue growth), Tiffany is heading in the other direction.

Perhaps proving that even the rich have their limits, Tiffany has had difficulty pushing through all of the increased costs it's been seeing. As a result, gross margin dipped by more than 2% in the fourth quarter.

As previously mentioned, Japan remains a disappointment. Same-store sales have been consistently falling in Japan for almost four years now, and the fourth quarter saw a further 7% decline. While some of the poor performance can be attributed to the still-sluggish Japanese economy, a bigger issue is that Japanese tastes appear to be moving away from the styles that have characterized Tiffany for so long. Worse still, this is all happening in an environment of a stronger yen -- a situation that should be helping Tiffany's Japanese results.

As management and loyal patrons of Tiffany would no doubt agree, Tiffany is a company to which few compare. While that makes its brand strong, it makes comparative valuation a bit tougher. Its goods are far more expensive than those sold by Coach or fellow jeweler Zale (NYSE:ZLC), and the firm's really not comparable to retailers such as Nordstrom or Neiman Marcus, either.

Nevertheless, these shares do look a bit pricey. The company's same-store sales are below those of other luxury retailers, margins are dropping, and the return on equity is nothing to write home about. Trading at more than 20 times trailing earnings with an expectation of low-teens future growth, this Fool would much rather own Coach or Nordstrom. While those two companies aren't cheap either, they are at least showing robust same-store sales growth and strong operating leverage.

Fool contributor Stephen Simpson, CFA, has no ownership interest in any stocks mentioned.