You can always tell when you visit a website that is using spun content. At best, the article reads like it was written by someone who doesn’t speak English as a first language and at worst you cannot even make sense of the text on the screen. As Google gets more and more advance, jibberish articles packed with links aren’t going to do your website any good and might actually do damage to your rankings.
Spin Rewriter integrates with almost any SEO software. This allows you to post high quality articles quickly and easily. The only drawback is that you only get something like 300 API requests every 24 hours. You can quickly burn through this if you’re doing multiple campaigns. The developer does not currently offer a plan for heavy API users but maybe they will in the future.