I'm not taking sides, just showing what I've found.
To quote a man who has been closely involved with car makers and oil for decades.."use a lubricant of the correct viscosity that is specified by the Manufacturer and Listed by them as Approved – especially when under any form of Warranty"
Of course, out of warranty, use what you will and be happy. But you won't go wrong doing the above.
ps, better RL or Amsoil than swill...synlube any day.
BTW, Exceeding the OLM is a warranty violation regardless of what oil you use.