Humans will pick sides. Something goes wrong, we must find someone or something to blame. Truth is (ouch! not the truth!!) I turned my 360 magnum over to 300k (now almost 308k) on QS changed every 5,000 miles. Guess what? Truck still runs as good as the day I bought it. With supply shortages, I have now switched to Valvoline due to availability. We pulled the main caps off of a 2.2 Lancer at 196k miles and they looked like new - QS was used. My brother-in-law runs Havoline. Went back to back to back to almost 300k using that oil with oldmobile and buick 3.8. My neighbor went 246k on a maxi van 318 using pennzoil before the van caught fire and burned up. Truth is, QS, Havoline, Valvoline, Pennzoil, Castrol, Mobil, every one of these are a good oil and will give your engine long life. But we like to pick sides and cheer, boo, and have claims of victory. LOL Now if your engine needs zinc, pay attention.