Stick with what it says in the book. TBH it surprises me when car owners don't seem to trust oil recommendations from the manufacturer of their car. And instead feel the need to consult motor factors, mechanics or internet posters - many of whom are full of sh*t and will come out with absolute garbage. Main dealers aren't immune from it either.
I have heard motor factors and mechanics recommending oil solely on the basis of the name on the tin "that Duckhams is great oil, I've been selling it for 30 years, I wouldn't touch Castrol with a bargepole!". Someone else then recommends Castrol and says Duckhams is crap. .Which one is right? Neither, they're both clueless. It's s similar story with viscosities, oil change intervals, manufacturer and ACEA ratings etc., lots of cluelessness.