Never recorded the total time so far or i just dont remember...
Because usually i have too many breaks with stuff to do in between a run, people quit, bail us or we dont make it in one day...
But i think we made it in around 5 hours or less once, was a really nice group and we got most objectives.
Just the pinch of evil wouldnt come no matter what... before lvl 67 finally.
So that we didnt have a real chance to get face the evil additionally. Never had that so far.
When there is more time again and a long lasting group i will keep an eye on it