"errbacks" definitely have benefits since having the error parameter forces you to think "where should I handle this error". With exceptions, people often get sloppy and let them be thrown and handled wherever, often at the wrong place.

Now it does make code more verbose since 90% of the time, the answer to "where should I handle this error" is "not right here" and with go/errbacks, you have to be explicit in that case while it is the default for exceptions.

For Javascript, I recently wrote a module that allows you to jump between styles very easily: https://github.com/bessiambre/casync#readme