It depends. I don't know of them ever sending someone. Some local dealers might send someone, but that's up to them.
It really depends on what the issue is, so you have to call them and discuss it with them direct.
If you read through the forums, you'll see they have exceptional customer service and they'll take care of you.
That's another reason why they like people to call them direct with issues as they don't monitor the forums (and I don't work for them, I'm just a moderator)