There is an interesting thread on the Norton forum about oils. So extensive bench testing going on. Jim, who is doing the testing and reporting knows a thing or two about engines.
https://www.accessnorton.com/NortonCommando/follower-scar-oil-tests.25898/
The results are interesting and still developing. But both the Guzzi and Norton engines are relatively similar in that they are air cooled, flat tappets and pushrods. The biggest difference is that the Guzzis cool better due to the V-twin format.