It may get pretty confusing if you're not used to transpilation, too. For example, when you want to instrument your code for code coverage for your unit tests, you need to map that instrumented code and its results to your typescript files and not the es5 transpiled version of your code to see which lines are failing/not being run/whatever. There are good plugins, but there's definitely some effort involved.
People on my team are using Angular2 in their own projects and are claiming huge productivity gains. They love the relative simplicity and power.
For example, my current company screwed itself by using a fork of UI Grid, and thus probably cannot upgrade the current app to Angular 2 easily.