Folks if an engine oil manufacturer DOES NOT specifically list Group IV and Group V components in their "synthetic oil" then the product IS NOT 100% synthetic. Rather, it is Group I,II or III petroleum base stock, improved refining as the Group designation increases. Manufacturers then add some true synthetic components such as some PAO's and other constituents to improve product performance and marketing tag lines. Show me the PDS!
Group IV products are PAO base stocks, polyalphaolephin. Look up PAO. Group IV base stock is used in conjunction with Group V stock which are esters: like polyglycol and silicone.
Superior to any lesser engine oil. I have seen first hand and cleaned oil GUNK deposits from Dino oils off of the interior of V8 engine blocks. True synthetic does not leave that kind of deposit. Turbo engines REQUIRE top quality synth oils for best performance and longevity. Look it up.
My research says GERMAN made Castrol Edge is a true synthetic since it is a PAO base. Apparently the Euro's have more stringent standards. But where can this be found in the US? I am searching. I soon take possession of a Volvo 2020 XC60 Momentum T6 AWD. Volvo says it fills the engine with Castrol Edge. Presume this is the Euro made stuff superior to US made Castrol Edge. Still I don't like the long 10k service interval. I will likely just go in for the free software update, which I guess is a good idea. Never had a car before that needed a software update.
If anyone reading this has automotive questions, message me. I am a former engine builder, bare block up. NOT THE expert, but I know a lot in general about auto maintenance and repair. If I cannot competently address your question I will say so. I read so much misinformation on car forums that I like to dispel misleading info where ever I can, if I can.. There are some folks on this forum who provide sound info.
I plan to have REDLINE true synthetic put in my car after oh, about 5k of break-in. True full synthetic oil is NOT recommended to be used in much older engines previously run on plain Jane Dino oil. True synth oils have components that can erode OLD seals causing leaks.