I've been using a Chromebook Pixel (64GB version) as my primary work machine since I received it in 2013, first running Debian and now Arch. You'd be surprised at how well it's held up:

-It only has 4GB of RAM, but that's been enough up to now. Most builds are I/O bound anyway, and the SSD is fast.

-I don't use an external monitor, as the high pixel density of the screen more than makes up for the small size.

-The 64GB can be limiting, but in some ways its been beneficial, as its forced me to actually pay attention to backups.

-These days, if I have a long-running/high-resource process, I just spin up a VPS and run it there.

I think Google was pretty prescient with the Pixel laptops. When this one isn't enough, I'll be upgrading to the 2015 model.