Imo it is not possible for google to detect properly spun content, it is not worth computing power it requires. They can do this using ngrams for example, but it is uses a lot of queries. And for example article spinner I coded beats this algo, so google cant detect that the content is spun. Manual spinning is also good but it takes more than 30 minutes per article.
Start with a quality article. This means a unique topic or viewpoint on a very specific topic. The information must be valuable to a human reader. At this point in time, it is not possible for any software program to produce content that is engaging. If you start out with a low-quality article, the chances are high that the alternate versions are going to be even worse.
From personal experience Spin Rewriter is the best! like I still use it today. Its so easy to use (Just copy paste and the program do everything) Because of this tool I managed to schedule content and articles for 3 years, do you know how much time and money I’ve saved?!?! A LOT!!! Also i high recommend you pick their mothly plan if you are still in doubt