Has anyone here tried "nomorobo.com" to stop robocalls?

I hate Robocalls. I am on the Do Not Call list but still get them. Someone told me about this service but I am suspicious. Why? Because I have to give them my email and phone number before they will tell me if they will block the numbers. That smells fishy to me. I want to know before I give out my info.
So, has anyone here tried it? What were the results?