Got 60,000 on my 2004. No issues yet, knock on wood.
I maintain the hell out of it though. I'm planning on another 60,000 before I rebuild the top end.
Evos are outstanding. Miss mine all the time. Sound much better than a Twin cam. They are simple and bullet proof like a tractor engine. Only thing that breaks is the inner cam bearing at 50k so ask, and if that hasn't been done plan to do it relatively soon.
$4500 for that bike is a good price. You'll love it.