I recently re-implemented the original Recoil demo app (from the React Europe 2020 keynote) using Jotai. My goal was to test how Jotai performs in a realistic app with lots of independent components and state updates.
The original Recoil demo is great for this kind of experiment: it renders many widgets (each with its own piece of state), simulates real-time interactions, and was designed specifically to showcase fine-grained re-rendering and subscription models.