Well it's nice when you stumble upon a very good oil and filter combo for a car. For the lady's Camry it was the Motorcraft synthetic blend and Wix filter. I have run PYB, Pennzoil Gold, and Havoline in it. The quietest it's run has been with the Motorcraft by a wide margin. It surprised me a good bit the sound difference between the Motorcraft and the other oils I had run in it. The Altima has run very good with the Havoline Pro DS 5w30. Runs has quiet has the Castrol gold bottle 5w30, Castrol 0w30, and Pennzoil Ultra. I am very pleased that I can usually find the Havoline on sale as well. I don't believe there's anything at all wrong with running whatever is in sale. That line of rolling with maintaining one's vehicles is fine due to the fact there are so many good products to choose from. I am not against trying another oil that would happen to be on a good sale. I haven't run Valvoline or Quaker State Ultimate Durability, Formula Shell, Kendall semi synthetic, yet in my car. So, I may well give them a try as well. But I have discovered 3 oils that work very well in my car with Mobil Super Synthetic a good choice 4th choice as well. My old Nissan Sentra saw nothing but Castrol Syntec 5w30 in it for over 120k miles. My Ford Fusion saw Valvoline Synpower and Castrol gold bottle 5w30 about 50/50% of its 70k miles. It's interesting to try different oils in my car. And it's good to find ones that do very well. It's not a one size fits all affair when it comes to this for all the different cars and trucks. What works well in one application may not do so well in another. Not that any major harm would be done by running a in specification oil in a particular vehicle. It's just another product may perform just a bit better than another at times. As an interesting side note a guy on the 350Z site did a lot of work compiling UOAs regarding the VQ 3.5 motors. And some oils did a bit "better" than others.