It was all quite smooth. If you've got an 8am appointment, you should probably arrive around 7:15am, to be at the front of the 'queue' for these more detailed interviews. A separate queue is maintained for the more frequent, less detailed interviews. I had about 5 people ahead of me... and therefore had to wait around 1.5 hours. Once my number came up though... it was mostly fast. Remember to bring the address that you want for return delivery of the passport though... as you can't bring phones/laptops into the consulate.