Shaving oil is very muich a YMMV type of thing.
Couldn't agree more. If it works for you, go with it. And this advice applies to many things with shaving.
I would also challenge the OP to try using plain old Extra Virgin Olive Oil in place of any pre-shave oil or shaving oil that he may be purchasing. It will likely work just as well if not better, and be 100th the cost