In a related matter: Has anyone built a production app with Exponent JS and lived to tell about the experience?
In general, people have been really happy using Exponent so far. It doesn't work for all use cases yet since we are still beefing up the roster of native modules that are included, but you can do most of the stuff that most apps need already, and we're adding more every day.
I'm super picky when it comes to UI/UX which is why I still prefer native on both platforms. But keep up the good work!
Here's a 2 minute video that I think explains what we're doing pretty well: https://www.youtube.com/watch?v=IQI9aUlouMI