Both the old and new Pennzoil conventional meet Ford's specifications, so I wouldn't hesitate at all to use it.
The only "issue" is that you're wasting money and natural resources unnecessarily. I'd simply follow the car's oil life monitor. It's there for a reason, and while it's relatively new versus GM's, it uses similar logic. It's a lot more accurate proxy for your oil's condition that time or mileage, and the upper limit of it (1 yr/10K miles) is very conservative.