Inter service communication: pub/sub vs message bus vs req/response

Over the last few weeks I've been going over a few different ways to solve inter service communication. So which one is best then?

Well as usual it depends... Personally I tend to stay away from the message bus as it becomes harder to detect when one component is not functioning the way it should. But if all components behave good and publish metrics you can actually monitor their behavior quite well making the message bus very attractive in its flexible glory.

So for me the choice comes down to how I can detect when a service is not behaving the way it should. And simplicity. A message bus for example always adds another layer of complexity which I try to avoid unless really needed. But it always depends - there is no simple answer...

What is your preference?