My own take:
Don't use engine (oil) treatment sa brand new or newly overhauled engine. After break-in or about 15k odometer reading pwede na.
I regularly used Pertua engine treatment from 1988 to 2003 in my old 1979 12R toyota corona wagon. The engine was running very smooth more than the nissan sentra of my neighbor. I scrapped the car not because of the bad engine but due to body defects.