Ranked in these QuestionsQuestion Ranking
Pro Chromebook hardware support baked in
Many things work out of the box that do not with other distros, such as touchscreens.
Pro Chromebook specific OS
Gallium OS is engineered with Chromebook hardware in mind to make the best use of Chromebook CPU's, limited RAM, and storage limitations.
Con Not the best looking UI
It's not the best in terms of UI but you can always install themes