If you have not used a spinner before then I would suggest that you first use something that require more human imput like The Best Spinner or Spinner Chief in order to understand the basic principles. However if you must go fully auto then I would suggest you go for Wicked Article Creator. I have it and understand it is similar to wordAI but a one off fee of $47.
"One thing important in my business as seo provider is to generate unique content for my clients. I used to hire many writers to produce many articles manually costing me lots of time and money. Good thing that I learned about this great piece of software, now I can have many unique articles as I want with just a few clicks.The Spinnerchief team rocks! Highly recommended product"