I'm currently in Beijing, China and have noticed that the majority of the domestic brand suits sold in large, relatively high end department stores contain 1% to 5% polyester and 95-99% wool. Are there any reasons why a small amount of polyester might be more desireable than 100% wool? Suits made of 100% wool cost no more (and sometimes less) than the ~95% ones, in the same stores and from the same brands. I've also seen a slightly more expensive suit with fabric: 86% wool, 12% silk, 2% polyester...why include polyester in a higher-end fabric? One brand had a 93% wool 7% polyester suit priced higher than a 95% wool 5% polyester suit. These are RTW suits in famous department stores by famous domestic brands and are priced higher than the MTM suits that most foreigners buy from the small tailors here. I won't pretend these suits are top of the line, but they certainly seem better in design and construction than similar-priced suits in North America or the small-market MTM Chinese tailors. The question is: why use fabric that contains a little polyester, when 100% wool seems to be the same price? Also...standard-fare "polyster suits" made with 75% wool 25% polyester sell for about a tenth of the price of the ones I'm referring to above. Same with the fake Zegnas sold on eBay listing 15% polyester.