High performance oil is tricky stuff (as your earlier post suggests) and so much is intellectual property so there is a lot of misdirection and snake-oil. For the age and length of time to spot the oil is no good, it is too late for most of us, hence you need someone with insider knowledge. In the past Shell were way ahead of the game: no-one else could touch their premium products. I suspect their Helix offering is probably similar but I have no evidence or comparators. Most of these synthetic oils were primary designed for long service changes. For those of us who are a bit more cautious with their engines and change the oil (and filter!) every 5k miles or less they are more than likely overkill. When I drop my oil and try to pinch it on my fingertip I can feel it is still doing its job. Any car I have had has rotted before the mechanicals let go. Colour doesn't help on a diesel (always black!) or on LPG (hardly any change).
But as you say on a lot of forums it is almost like a religion, driven by belief in the lack of any concrete published evidence. People have their favourites that haven't let them down but I suspect most are pretty similar unless you go for the real bargain basement stuff or the extreme top end stuff.
If I had the money and wanted the best I think I'd have a punt on Shell (no affiliation), purely on historic track record and in the absence of any more recent data. Until then I'll stick with cheap and chearful Smith & Allan, something like
https://www.ebay.co.uk/itm/10w-40-S...ine-Oil-ACEA-A3-B4-20-Litre-20L-/252471326993
