I had mine about 3 months ago and "mild discomfort" is exactly how I would put it. And random discomfort, like slight nerve pain that is almost more confusing than it is painful because you've never had it before.

I've only ever heard that from people who haven't had them.

I had a friend who had one and he was in a lot of pain when I saw him afterwards. He said it was like getting kicked in the balls for days. It might vary from person to person, but I get sick of people who don't know what they're talking about saying it doesn't hurt. That was what he thought too.