Ember follows in the Rails tradition of "convention over configuration". This means common activities can be done with a simple command, creating a file, or adding a flag in the right place.
This comes at a price: everything that happens in your Ember app is deeply tangled in Ember internals which are very complex.
This means adding behavior leads one of two places: It Just Works, or you have no idea what is happening or what to even ask.
When you are an Ember beginner this second state can last for days or weeks of frustration. As you learn about Ember internals, it happens less often and you move through it quicker, but expect this to take months or years.
The Ember team has taken steps to mitigate this difficulty: adding great error messages, and adding great documentation. But it a fundamental downside to the architecture they have chosen. And it's fundamentally at odds with what I would consider the Node Ethos, which is small packages that do one thing cleanly.
I would recommend Ember to professional developers who have the time to really learn about its internals and can afford to lose a week here and there to tricky debugging challenges.
I would not recommend it to developers working on small projects with tight deadlines.