Yes, we had our interview last week. Arrived atleast 30min earlier. they will not let you in before that. Did not have any parking problem though it was paid. No camera phones allowed into the building.
Appt was a few minutes late but each of our interview lasted about 30 min max.
They had lost my greencard paperwork and my file was practically empty. They had no clue what to do but then made a copy of my greencard stamp and approved my case.
There is one asian guy who is a tough cookie and was asking my wife all kinds of questions. Be calm and patient since there might be difficulties in understanding their english.
Good luck