Asus Zenbook UX31
Equipped with 1.7GHz Intel Core i7 processor and 4GB of RAM, the device, like MacBook Air 13, has 256GB SSD. It runs Windows 7 and in the PC mark test it scored an average at 4077, while in 3D mark it mustered a passable 3696. The battery is a real stunner as it lasted an impressive 6 hours in battery mark test. Overall, it is a stunning ultra-book with brilliant sound quality, display and build. But, ports have been generously endowed in it. Not only, it includes the regularly used USB 2.0 port, headphone, microphone jack, built-in card reader, mini VGA, micro HDMI port, USB 3.0 but also includes an Ethernet port, a rarity in many ultra-books including Macbook Airs.
Bottom-line: Zenbook is the one of the slimmest ultra-books after Macbook Air, making it an ultimate traveller's choice. It has more ports than Macbook but comes at a similar price.
Acer Aspire S3
This is an ideal ultra-book with a blend of both SSD and HDD experience. Powered by Intel Core-i7 processor and 4GB RAM, the latest Aspire S3 has been upgraded with the latest Ivybridge processor. It is ultra slim and despite the metallic build, it is an ultra-light device weighing just 1.3kg. It boasts of USB 3.0 ports and an HDMI connector along with an audio jack and multi card slot. Battery life is not the best but almost touches 5 hours. In the performance tests it is an impressive performer with scores of 9473 in PCMark and 3029 in 3D Mark. It boasts of 500GB HDD and 20GB SSD, which brings solidity in terms of storage and performance.