To be honest I don't know all technical things about Face Oils, but I know they're really good for the skin, just like certain oils are really good for the hair! I don't think they're much different from Olive oil, maybe just some extra added things!
I have! I have tried coconut oil, grape seed oil, and rose hip oil on my face as a moisturizer. I loved all of them but found that I liked the rose hip oil best since it is not as greasy. My skin has been clear ever since I started to use more natural moisturizers on my face. Give them a try and see what you think!