The ease by which we can define our own routes easily without writing any custom route mapping rules (using URL Rewriting).The service stack has all needed features out of box like : authentication/authorization etc., I use this to build RESTful webservice in.net C# using JSON format data as output from my database table into XML file or HTML page so that people could access it through different OS systems too with proper formatting done automatically at runtime itself! So far everything works fine but if your requirement goes more complex than above then you would need some time as its not easy task. You should have deep knowledge about coding before getting started. Its good approach because now there are few new frameworks available where they provide such feature set as same level of freedom as given here while developing API's! It's not hard to set up - there are good documentation and examples, including an entire tutorial. The documentation could be improved. I have found that the syntax can get confusing when you're new to it. There is also a bit of a learning curve if you're coming from other languages. We used this for a REST API with JSON and SQL Server. It was easy to use and allowed us to quickly build out our API.