Mugen Seiki Super Silicone Shock Oil (50ml) (550cst)

It's a good silicone oil. I’m not going to say it’s superior to other oils on the market, but I do appreciate that it uses cSt for viscosity rating, which means I can count on the consistency of Mugen Seiki oils. It's also great that there's a wide variety of viscosities available. The only knock is the price. You're basically paying for availability and its viscosity range. Is it any better than Tamiya's oil? Probably not, but finding the full range (narrower range) of Tamiya oil outside of going to the source isn't reliable (and Tamiya USA is SLOW, and their customer service is essentially non-existent).