I've been using this service on my dev laptop, tablet, and phone for a few years now. It works well, and every time I turn it off, I immediately notice a huge difference as it blocks so much garbage that brings my phone's browser, especially, to a crawl.

I have never paid a cent for it. I still don't understand how they can make money... unless I'm actually the product being sold (which I was always under the impression that they didn't sell or share user data). Who knows.