Yes, we're using Elm in production for two years now. Rewriting legacy Ember application into Elm, and it has saved our sanity. To be honest, we dread the JIRA tickets that concern Ember and not Elm :D
Re deeply nested components: we have components about 2-3 levels deep, and while it's a bit more code and boilerplate than having a flat model, it's been just fine. Don't worry about it.
Re deeply nested components: we have components about 2-3 levels deep, and while it's a bit more code and boilerplate than having a flat model, it's been just fine. Don't worry about it.