It will not cause cat converter poison unless your engine is burning gobs of oil, in which case you probably would not be using this pricey oil anyway. So forget about that rediculous rumor that some people keep repeating. Also, this oil has a low volatility, meaning that very little oil will boil off over time. So your cats are safe. Meow.
This oil is CI4+ HDEO and therefore has elevated levels of anti-wear additives- more than your engine actually requires. So you are in the overkill zone there. This oil works great in a hardworking V8 gas engine, and will keep it alive a long time. I know of one 6.0 engine, same year and make except in a van chassis, that currently has over 400k miles on the original 6.0 engine using this oil. Vehicle and route have been sold and to our knowledge is still being used daily on a Fed-Ex Home Delivery route, but probably using another oil now. The rest of the story is that he was going 20-30k miles before changing this oil. Sometimes he would just change the oil filter in the middle or at 10-15k miles wih the previous SDF filters. I thought that was way too long, but the engine did stay running all day long. Before he used the HDD, he was going to the qwik-lube using bulk 10W-30 and changed every 2 weeks.