When Brian Winch started writing for RC Report he did an article about Castor Oil, good lord, the replys from readers that used Castor was something else, Brian needed body guards if he ever came to the states, every one had a new rope waiting for him. I use power Master fuel and it's oil is blended too. No real big deal for me, I use the fuel I can get at a good price, if it has a little Castor OK, if not, OK. I have run both Omega and Cool Power and never noticed any difference in how my engines run, both good fuels. Come to think about it my engines have never met a fuel they didn't like.