Pennzoil filters are Purolator made, QS were Champ last time I checked (but it has been a long time since I looked).
As for comparing Pennzoil and QS, they are similar, but not the same. Conventional are very close from what I have seen, but Pennzoil is the top tier product, with QS (and then Shell) being the budget level oil.
There have been rumors that QSUD may have some GTL base stock if SOPUS has extra.