Here's a process you can follow to decide, though:
1. Find a laptop you like that's in your price range.
2. Buy the laptop, making sure it has a no-questions-asked return policy with no restocking fee (Amazon, Microsoft, and certain OEMs all have this). I think the Dell XPS 13/15 are good places to start, as Dell officially supports Linux on these.
3. Try your favorite Linux distro by booting "live" from a USB drive. Ubuntu is a good option for laptops because you can usually Google "ubuntu [insert problem] [insert laptop]" and find a forum post about it.
4. If Linux doesn't work well enough for you, return the laptop and start again at step 1. I haven't so far had any more issues with Ubuntu on a laptop than I have on a desktop, so I don't know that you'd have to do this many times. To be honest, though, the problems on both laptops and desktops were too great, and I finally switched back to Windows after 5 years. Your mileage will vary, I'm sure.
Really? That's odd. Is there a parts sheet that lets you check which module the Windows version uses?
All the special function keys work, battery life is good, sleep works, etc. The only imperfection is that after I close the lid and it goes to sleep, when I reopen it, it forgets that I've disabled the trackpad, so I have to press the function button that disables the trackpad each time it comes back from sleep (I use an external mouse).
Edit: I have a model with 8GB RAM and SSD, but some models have less RAM and solid-state drives.
I have a C720P. There are two versions. should you have the older version (cyapa touchpad module), any modern kernel will work. If you have a Elan touchpad (i.e. touchpad doesn't work on boot), you'll have to patch a kernel driver. I could create a full overlay for my gentoo modifications, but I doubt anyone would want to use it. :)
Debian has worked great on both.
EDIT: I almost forgot that the X220 front bezel warps outwards in even the slightest cast of sunlight on a nice day. It's pretty alarming when it's not expected.
Great keyboard, nice 1080p display, trackpoint, (hot)swappable batteries and several storage options.
The trackpad sucks and RAM runs on single channel though.
That said, aside from the memory issue.. I love this laptop.
It is very lightweight and battery life / support is good in Linux Kernel 4.x
My configuration is about the same[] with SSD, and I'm super happy with this for my Linux/Virtualization development environment.
[
] I'm using T440s, by the time I got this last year in OCT-2014, the T450s, which is reverted to the sensible clickpad (with "two right and left clickers"[1]), wasn't released yet.[1] http://www.engadget.com/2015/01/04/lenovo-thinkpad-x1-carbon...
Low power CPU, plenty of RAM, large enough SSD, 1080p, and a matte screen. As I spend most of my time in remote SSH terminals, the Core M doesn't bother me. It is lightweight and fast enough.
I am looking forward to the updated Zenbook, supposed to be released this quarter.
Also, the price is right on.
