To rank your website in search engines you have to post content at your website on daily basis. If you have more than 2 websites then it is almost impossible to write unique content on all those websites. Because for proper blogging you have to keep an eye on word count of your blog post. To do this task webmasters use article spinning tools so that they can post articles to their domains daily. Paraphrasing Tool is also used by students when they have less time to submit their assignment; they just copy content from the internet, rewrite it, remove grammar mistakes and submit it. According to the webmasters, we have the best sentence rewriter tool available online.
Google is getting VERY good at catching spun content so you'd better be talented at manual spins. If they DO catch you, of course they'll spank you... and hard. So anything you use spun content on is inherently AT RISK. Worse yet... Google gets better at finding spun/poor content every year. So in the longrun you're screwed. I'd weight your other options and see if you couldn't find a cheaper source for manually hand written content.

Don't you hate it when your synonyms make no {sense|perception}? Don't settle for the "content garbage" that most spinners vomit out. WordAi can tell subtle differences between words and makes sure each synonym it picks makes complete sense. This gives you articles that are automatically readable, without you needing to spend countless hours fixing them up!