[dotancohen]

  > Another upshot of this is that with rarely driven vehicles, you might as well use
  > the cheapest oil which meets appropriate specs, because your oil changes are driven
  > by additive depletion and oil contamination rather than breakdown of the oil itself.

The Ferrari gets the cheap stuff, the Kia gets the good stuff. I love how some things are so unintuitive.

I just ordered an oil testing kit from Blackstone. Thank you for the idea.