Avoiding fake clicks on your Facebook ads

From an email I got: "Inspired by the viral video explaining issue of fake accounts clicking facebook ads, we have created a tool called Fan Harvest where we let you target your ads at people who have been actively engaging, a trait that only belongs to genuine accounts, with your competitors. Try us at http://fanharvest.com/ and let us know what you think." Looks legit and I know the team is strong behind this one.