So to sum up, ASL Amsoil 5W30 oil (API rated but not certified) is not that good for engines with catalyc converter and therefore should not be use (at least not for a long time) on the Rogue.

On the other hand, the XLF Amsoil 5w30 oil (part of the XL-7500 line?) is API certified and therefore can be use on the Rogue.

Am I right?

Do you know if the XLF Amsoil 5w30 is a full synthetic oil (group IV) or a 'false' synthetic oil (Group III)?
I noticed on the Amsoil website that they proudly say that the ASL oil is "100% synthetic motor oil" but for the XLF oil they only say "Extended Life synthetic motor oil", no 100% synthetic on this page.

They are all so vague that I become suspicious on everything now. Bad for business not to be 100% honest.