Sorry - that should have been "or". We would choose the one from those carriers that works for best for us.
Each of these carriers already have a plugin. I haven't implemented any of these for the normal selling of products because we have a separate process for shipping.
I was hoping that one of these plugins could do what we want because I want to automate the process for getting the shipping label to the customer. If we cannot automate this, we will just have to create the labels outside of nopCommerce and then load it to where customer can download it. Not exactly automatic, but it's a solution we can work with.