If your competitors have stolen your content and are profiting from it then do everything you can to get it removed! DMCA, write to the sites, write to the hosts.
Do NOT move the content to an archive URL before doing the DMCA or Google won't know that you originally created it. This happened to us - another mortgage broker stole some content from one of our main sales landing pages, we didn't notice until after redesigning our website, and of course our new urls had a later date stamp than the site that stole our content so our listings started to drop (whole site, not JUST the page that had been copied). We got the listings back within a month of filing the DMCA, but still, it galls that our content may have persuaded customers to contact the other company! They should have been our customers!
By all means rewrite/refresh the content if its 2 years old, but do it as well as the DMCA.
Good luck with this - I feel your pain,
Amelia