Xiaomi on Wednesday unveiled the Mi Notebook Air, its challenger to the MacBook Air. The 13.3-inch model is priced at about $750, compared to the MacBook Air's $1,050 price tag in China. The device is also available in a 12.5-inch version. The Mi Notebook Air offers a number of features that aren't available in a MacBook Air. The 13.3-inch model is gaming-ready.