Unless you only buy one share 6 cents downside risk is the exact same as $60 or $600 (or $139 or any number you choose). Or are you recommending buying one share of PTSC?
You can buy 10,000 shares of PTSC, 100 shares of P&G, or 10 shares of Google with the same $6000. Now compare downside risk...
The OTC is littered with stocks that had little "downside risk" at 6 cents that are trading in trip and quad zeros.