I like how they are able to provide real life examples of their work, which helps me understand what's being built much better than just reading about it in an article or book! There was one time where my team needed help with some technical documentation for our product but didn't have any resources available at the moment so we had them use another example from there portfolio instead (which wasn't something related).
That really made us realize why having your own docs would be beneficial - even if you don't know exactly how yours will look yet because no other person has done this before :) We were also looking into implementing more complex integrations between different systems and services by using APIs rather then code-based methods. They helped implement many API calls as well as build out new features without writing too much custom integration ourselves.