We're using it in production apps since 18 months, and even if it still sometimes feel like it's a 'beta' (interfaces change, navigation keeps changing too) it has become more reliable. The real struggle has more to do with XCode and native apps in general (Expo definitely fits in the prototype thing in my opinion).
The good (great) part comes from the fact we're a small team (4 devs) and and thus we can do / test / debug things only once for our different platforms (we're using Electron, with all its caveats too).
Apollo and GraphQL availability is also a great plus.
There are performance issues, and data transfer from RN to Native code and the other way is complicated (and different on each platform).
With 30 persons working on an App you've got more than enough to have 1 version for each platform though.
The good (great) part comes from the fact we're a small team (4 devs) and and thus we can do / test / debug things only once for our different platforms (we're using Electron, with all its caveats too).
Apollo and GraphQL availability is also a great plus.
There are performance issues, and data transfer from RN to Native code and the other way is complicated (and different on each platform).
With 30 persons working on an App you've got more than enough to have 1 version for each platform though.