A Pinebook is basically an open source ARM laptop that ships with Linux by default. So far the OS used to be Debian but they seem to have switched to Manjaro KDE. The latest Pinebook Pro is already available to pre-order.
The pros about Linux laptops is always the compatibility, so you don’t have to worry about how well Linux is supported, you get full support by default. There are currently 3 images available for Pinebook Pro, KDE, XFCE and i3 version of Manjaro, the default is KDE.
Pinebook Pro can be pre-ordered here: https://www.pine64.org/pinebook-pro/