Your looking at old Quaker State. It is now SM rated.
But to answer your question, I personally would choose the Pennzoil. It uses a different base stock (Group II+) and I believe it has a better additive package. The blends are about the same, but in the High Mileage oils I would again choose the Pennzoil over the Quaker State. On the synthetic side I like the new Pennzoil Platinum better.