I never liked QS but used lots of Pennzoil over the years without issue, I always considered QS the bottom rung of quality in oil.
Though today with the cost and as much as I go thru, I find myself doing something I never thought I would , and that being to buy the "house brand" on oil, usually at farm and fleet.and at that only when on sale and I "stock up " then.
Used to use lots of Pennzoil and Valvoline.
I recently bought 4 cases (6 bottles per) of Valvoline high zinc for break in purposes