I've been a PO at the same company for a long while, the difference is, the PO is responsible everything except portfolios, sales prices, and courting customers. Once contact is made, we take over. We help with pre-sales planning. But the portfolio, price, etc is not on the PO.
This leads me to the PSPO II test. The test is difficult and scenario based. But, I am perfect or doing extremely well in all sections except: