I use Mobil 1 syn and Mobil 1 filter from the first change on. Also change both at the recommended time. I've never known if syn oil really made a difference other than it cost me a lot more. This was a good confirmation of syn oil. But more importantly of regular oil & filter changes.
2003 Acura TL Type S with 255K miles when given to our 16 yr old grandson in Feb 2024 as we moved to UT from CA. Zero engine issues from 2003 to now. I loved driving that car. GREAT car! He says it still runs, so that's good.
2014 Honda CRV with 116K. No engine issues so far.
both cars have syn oil and filter changed every 7500 miles.