I don't know if you can Actually say, "Which are the Best Countries to Advertise?" It Varies each and Everyday. Of course, the United States would be Number One. I Believe it's How you Advertise, not so much as Where. Research some of the Statistics and don't Limit your Advertising to just one Culture. SFI'S Growth Tab shows the Cornucopia of how many Different Countries are involved with SFI.