Will Google Penalize Me for Using the Same Content as Other People? (Duplicate Content Penalty)

Nobody understands the inner workings of Google but Google themselves. However, a duplicate content penalty only really exists for putting duplicate content on multiple pages within your own website. Using the same content on different sites, or different people using the same content on different sites, does not carry a duplicate content penalty. That said, by adding to and enhancing the PLR content you buy, you may see better results.