I tried Crouton and found it too awkward, so deleted ChromeOS and installed Ubuntu from an SD card set up in the normal way. Things will not work right out of the box. You need to make a recovery SD card in case you accidentally drain your battery:
http://dev.chromium.org/chromium-os/developer-information-fo...
Do not skip this step, as it is possible for a crash can put you in the same state - it happened to me.
Your machine will probably reboot when you try to suspend/resume. The fix varies depending on the kernel/Pixel model; I fixed this by adding
tpm_tis.force=1 tpm_tis.interrupts=0
to /boot/grub/grub.cfg (and remembering to run update-grub).
You need to add an .xmodmaprc file to your home directory to get the hardware volume, etc. keys to work. After rebooting, sometimes this doesn't "take" unless you log out of the desktop and back in a couple of times. I can suspend by running "pm-suspend" and wake up by opening the lid, but suspending by simply closing the lid doesn't work. I'm used to that, as it was the same deal with my Ubuntu Thinkpads. You can probably fix that if you care enough. While you're setting up your keymappings you can also change the "search" key to cntrl, etc.
I plan to put up a more detailed guide on my website eventually (it has an Atom feed).
The Pixel is a pleasure to use all day (but gives me only five hours of battery). Don't be put off by the small SD drive, you can use the convenient SD slot to supplement that.
I think I'm going to buy a used 2013 version as well and setup Linux on it. Thank you!
I like running Linux with multiple shell windows along side Chrome OS, but for me having a good emacs setup and Haskell, Clojure, and Ruby installed is fine. I also use nitrous.io for development.
If you have time to try out Codeanywhere I would love the feedback. Thanks!