I also have a ASUS Zenbook Prime. I bought it based on Jeff Atwood's glowing recommendation on his blog. I am running Ubuntu 13.10, which fixed several hardware issues and possibly introduced a couple more. Here are my main issues with running Ubuntu:

1. Ubuntu does not remember screen brightness after reboot.

2. Getting Flash properly installed so I could watch Amazon Instant Video was a struggle. Netflix over Wine works like a charm if not ideal (it's broken for me a couple of times but it's working again now) and HBO GO works even better.

3. Firefox does not seem to support high DPI screens for Linux yet. So you either have to zoom on each page or use an add-on such as NoSquint.

4. The SSD is apparently too fast for lightdm, the logon software, to handle. I had to change the default logon software to gdm.

5. Frequently, the feature which saves Facebook/Google/Twitter login info for desktop apps would forget my password and generate blank popups and error reports.

6. Random error popups every once and a while.

All of the above are minor gripes considering I am not paying anything for this software. Overall, I am very happy with the entire stack from Ubuntu to the Linux kernel. I choose to do most of my home desktop activities on Ubuntu when possible. I keep my Windows desktop around to run iTunes and that's about it. I like the Ubuntu/Linux experience but the above problems prevent me from recommending it to my family.

Issues with ZenBook Prime:

1. Touchpad is not great.

2. I have hardware problems with the keyboard and the power and I've had to send it back to ASUS for repair. Seems to be working fine now.

You're right; I would not recommend it to my family. At the same time, that's not how I measure hardware for myself or other people who have worked with Linux.

Change the layout.css.devPixelsPerPx option in about:config to deal with the zoom/dpi issue.

6 hours being good depends on your frame of reference. It's half the battery life of the Macbook (12 hours for the current model).

The zenbook looks like a competitor, but I'd need to be sure that it's built as solidly as the MBA. The MBA is even thinner and for about the same price you get hardware that is incredibly well designed and manufactured.

For me, I've learned the hard way that going by raw specs alone is a poor way to judge a laptop (desktops are another beast) -- it's the build quality and the little things that make or break the pleasantness of the experience.

Comparing the Zenbook Prime's battery life to a current-generation Macbook Air doesn't tell you anything about ASUS vs Apple. It just tells you that Haswell is much more power-efficient than Ivy Bridge, which should have been obvious.

ASUS and other manufacturers should be out with their Haswell refreshes soon enough. Then you can make a more meaningful comparison.

Fair enough, but I wasn't trying to make a claim about ASUS vs Apple. I was responding to his question about 6 hours being "good".

The previous generation Macbook Air (Ivy Bride) still gets more at 7 hours anyway.

Fair enough. I didn't realize the new MBA was so far ahead on battery life. While most of the build has been solid for the 9 months I've owned it, the durability of the power plug (an element that can hose the computer) worries me.

Coming from a 12" ThinkPad with 1024x768 screen, the 1080p sold me on the ASUS. I'm sure the MBA will get "Retina" display screens soon though.

I've been getting 9 hours on the Zareason Ultralap running LMDE.