Seems to me, that based on each individual's research and experience, and recommendations by those whom we know and trust, each person has their "favorite" oil. I built plenty of "L" series motors in the 70's and didn't pay much attention to oil other than we used non detergent oil to break in a new build (so the rings would seat properly). However, if oil producers were adding ZDDP then, and then were forced to remove it, I think I want that in my oil now (just me). I still think that the most important aspect in breaking in a new valve train is plenty of flow and an oil that clings to pressure points. Make sure that all t's are crossed and i's dotted to make sure that happens. Fill your oil pump with oil before installing it and liberally coat the pressure surfaces with a quality prelube (which most contain zinc supposedly because it clings and coats metal better) and make sure you have oil flow. If you want to use something other than ZDDP additive oil, more power to you.....you may be fine or you may not. Your choice......my choice is VR1.