Flat Tappet Lifter Oil ??

Ive rum Mobil 1 10w30 High Mileage in my (gasoline) flat tappet engines for a couple years now with no problems. It's an ACEA A3 rated oil. I send a sample in for analysis at each drain interval, and my iron numbers have been well below average.

For break-in, I use dino oil with an additive and switch to the synthetic at first drain.