Yea mate, WordAI really is overpriced IMO too, which is why I didn’t rank it higher in the cost-effectiveness rankings. Now, it did change more than a few words, but I see how you would think it’s less than 80% unique. TBS is also great, but only in terms of functionality and the easy interface which allows manual spinning to be done quite fast. As for their thesaurus, I think they have a lot to improve.
Never let your audience guess what you are trying to say, your writing should literally speak for itself. When your content has too many errors, it becomes difficult to read and understand. Although, one or two errors can be skipped by readers, but glaring grammatical errors can minimize the impact of your content. Also, it can make your writing difficult to read and digest.
There are a wide range of applications that might benefit from the content rewriting capabilities of ArticleRewriterTool. The obvious applications include building content for your website or blog. Other applications include any kind of essay or creative writing (virtual or not), twitter, newsfeeds, Craigslist posts or even paid article writing services.