Whatever you may think but Google bot is most genius in term of web related work – so if you are thinking to ditch it with the rewritten content then I am afraid it will require much more than that.
If you hire people to do it manually – they should be of great quality because most of the rewriting people – just use the software to rewrite the content and they just rename some of the words to make it unique – its basically writing synonym for the words.
This was workable some years ago and Google would have happily listed you and also rated you higher in the search results – but with times change Google bot has become smarter enough to catch the two contents present in their database that the written content is actually a unique one or the synonym.
Same rule applies for the wordpress plugins – you could find n-number of plugins available in the plugin area of wordpress to have your content re-written – most claim that they are the best.
But truth is that all use same rewriting style – synonym to make it a unique adaptation. There may be some better plugins for rewriting and few of them herded in the paid territory also.
See, the foremost thing you are doing with this rewriting plugins is you are making fool of Google bot – I am not concerned with any other search engine – because others will still index.
I do recommend not using these plugins any more – but if you still craving for them – so before applying or buying do see their demo once – and try to differentiate between the two articles present – the original one and the rewritten one in the demo.