I'm using Joe Gibbs XP0 oil, a Facet cube pump ( good for all of 7psi) and an alloy catch tank.
Oil temp. sits at about 50 degrees. Pressure is interesting as it sits at 5 psi on idle, drops to 3psi as the revs increase, which looks as if the charger bearings start to suck in the oil, then rises to 7psi above 6k. Looking at a Walbro fuel pump at £85 giving 15psi.
What Pim said about particles in the oil is true. When I first ran my standalone, it flushed a very small amount of micron dimension ferrous material from the charger which attached itself to the magnetic plug in the catch tank