[mjallday]

What are the issues that you've run into?

We've used Ember.js to build a reasonably complex app (github.com/balanced/balanced-dashboard) and while there have been some tricky bits it's generally been what we expected it to be.

Ember.js does a great job of helping you when you start to get a lot of moving parts. I felt the same way you did before I dived in but now I'm comfortable in saying that its possible to build large apps in JavaScript.