Wow, Jen - It's a massive question!
I haven't confronted the person who raped me. I don't know who he was.
I also don't know that I'd want to, nor do I know what I'd say if I was given the opportunity. I think the theory of what you might want to say is very different to the reality of actually doing it.
There are people here though, who have confronted their abuser, and I think it can be very helpful. I know of people who have sent letters, and remained anonymous by doing so. Also, of others who have 'confronted' their abusers in court.
I suppose it depends on the circumstances, and how they are confronted. Most of all, it's important to stay safe, please ;) . I can imagine that it could be very empowering for the survivor, so long as it's 'safe', and you have support to help you deal with emotional aspects.
Their response is the unknown, which I suppose could be damaging to the survivor. It's a tough one, certainly.