I'm going to get downvoted for being honest ... I usually do.
I bought a refirbed MacAir 2014 edition for about £630 ish entry level with the same warranty as the new. It would be interesting to see how Asus pair up with that a few years down the line.
First things first, I bought the Air to be light, I could carry it with me easily and do writing whenever the inspiration struck. It looks like the Asus could actually score for me, because I use many different machines and the Mac keyboard drives me insane. No home/end/pgup/down, etc. I have Mint 64 bit on there and that saved me a little by returning the keymappings to more or less standard ... so at least I can touch type again now, without thinking too much about things. (the speech quotes over the 2 did my head in ... or lack of them, rather)
The Air can run Portal 2 quite happily and that wasn't in their list. However, if it can run Crysis I suppose the Asus should be up to the challenge.
One thing that I would have liked to hear about, is a comparison with the screen of the Asus and the Air for crispness and quality. How did that compare?
Got to admit that I do use the backlit keyboard a little, but not much, so it wouldn't be a deal breaker for me. (also I need to learn more about the change in scripts so I can fire off the backlight command more quickly during boot) I don't like the "light" arrangement as per the thinkpad.
Just for the sake of getting a feel for things, if the Apple sound is 10/10, then what rating would you give the Asus? 7/10 ? 8?
Have to admit that I've only had the Air for ... oh, some months now ... so I won't be shelling out for a replacement ... but my mind is currently thinking that for those that want/need it, the price difference might be worth the screen/sound/backlight improvement?
I'd still look for refirbed some time later, though. I think I'm done paying full price for the smell of new. Apple's 1 year against some places 3 months, however, does still tip me Apple's way ... well, it would have, but the keyboard arrangement means I'll actually never buy Apple again. Once this Air has worn itself out, that's it.