Can someone explain the difference between RSO CBD and, well, regular CBD oil? [View all]

The place I'm now ordering from sent me a product email and RSO was one of the items listed. I did a little research, but the only thing I came away with is it's maybe just a different processing?

Anyway, I just placed an order so won't be placing another for a month, or so, but now I'm curious if it's something worth trying.