Very easy and you seem to get prioritised to go straight through the queue. I got the impression as long as all your paperwork is in order there will be no problems.
Interview lasted about 5 questions and felt more like a formality. Visa came very soon afterwards.
Some people described them as being extremely friendly but I didn't find that to be too true. They were very professional and courteous which is all you need.
Consulate / USCIS Member Review #17035
Review on June 11, 2015:
