When comparing Chromium OS vs PrimeOS, the Slant community recommends PrimeOS for most people. In the question“What are the best Linux distros that don't use systemd?” PrimeOS is ranked 25th while Chromium OS is ranked 30th.
Ranked in these QuestionsQuestion Ranking
Pro Minimalistic interface
Chromium's system UI uses as little screen space as possible by combining apps and standard web pages into a minimal tab strip: While existing operating systems have web tabs and native applications in two separate strips, Chromium OS combines these, giving access to everything from one strip. The tab is the equivalent of a desktop application's title bar; the frame containing the tabs is a simple mechanism for managing sets of those applications and pages.
Because Chromium OS is designed for users who spend most of their computer time on the Web, it is intended for use in computers with little local storage and fast boot-up times.
Pro Safe and requires little to no maintenant
Since you only have the browser, you cannot install applications (outside Chrome Apps which are decently protected by their limited API and the Chrome Web Store). This means no harmful virus, and also nearly no way you can screw your system. Everything will just work.
Pro Dual boot at single click with PrimeOS installer
Pro Standalone OS, better performance than any emulator
PrimeOS is standalone OS thus provides 2x performance than any emulator as emulator runs on a host OS.
Pro 3x better performance than windows budget laptop
Pro Android Gaming on PC
PrimeOS is equipped with a key mapping tool, DecaPro whihc let you play any Android game at the comfort of keyboard and mouse.
Pro Android Ecosystem with Desktop Interface
PrimeOS provides access to the whole Android ecosystem with complete desktop interface. Now use multiple apps on single screen with minimise, maximise and close option.
Possibly harms your privacy.
Con No auto-upgrade (unlike Chrome OS)
Chrome OS auto-upgrade the system, but Chromium OS does not. It's possible that they're thinking about adding that feature from the design doc.