I worked with both. Without going into details - I recommend TS as it's better documented and easier to work with. With 3.0 they also improved error messages.

I worked with both. Without going into details - I recommend TS as it's better documented and easier to work with. With 3.0 they also improved error messages. EDIT: one thing I miss from flow is https://github.com/gcanti/babel-plugin-tcomb https://github.com/gcanti/babel-plugin-tcomb - it's quite handy to spot data errors (before you have big static coverage)