What Oil Do Experts Recommend For A Benjamin Recharge?

I'm using 'Powermate PX P018-0084SP 100% Full Synthetic Air Compressor Oil' which I picked up off Amazon. I normally don't start any 'engine' off with synthetic until after break-in, but a compressor is different and there was no prohibition in the user manual.

I saw no appreciable color change of the oil, but I did my first change at 2 hours of use. Looking in the pan at the drained oil I did see little sparkly flecks like bits of break-in metal so I'm glad I changed it. I'll probably do another short change after the next 2 hours, and then go onto a more standard schedule. Oil is cheap, relatively speaking.