I used Fraud Blocker at the launch of a Google PPC campaign. Within 30 days, they saved me ~50% in fraudulent clicks, which is more money than the cost of a max stack. You're just wasting money if you're not running fraud protection on paid campaigns. Even on small campaigns, this will pay for itself.
The interface is modern and easy to use.
The Facebook integration has been a little bit of a pain, but it's worth it. It's in beta, so it will likely improve with time.
Knowing that API and white labeling are coming, this is a gem. Great work, guys.