My wife drives a 2011 Porsche Cayman Hybrid with the Audi V6 supercharged engine. Oil is spec'ed as Porsche C30 5W-30 and I have been using Mobil 1 ESP or Liquimoly 4200 5W-30 in it. The car now has 100k miles on it and warranty is long gone. Can I safely switch to something like a Castrol edge 5W-30 oil and move on? Something that is Gen 2 Dexos approved to protect the intake valves on this DI engine to the greatest extent possible? Rational is to be able to get a cheaper oil available at Walmart and other places.