- Flow has more & better type definitions for React than TS. I think it's because a lot more React devs use/develop Flow and also both are FB projects.
- For our Redux + Flow setup, we export an ActionCreator type that is a union of all action creators we've defined. This union gets refined by the switch statements in reducers, allowing us access to well typed action creators in reducers, without having to deal with import/export of individual types.
- The docs are pretty good. Several of my colleagues are new to static typing, and have picked Flow up easily because of the docs. I also heard some interest in providing video courses like Egghead.
- Flow has an amazing type system compared to Java. Except for enums though. Java Enums are much much better.