Quick and painless.
We brought all documents, they only took a few and returned everything to us.
Cell phones were allowed inside.
Actual interview was probably 5-10 minutes. Most of the time was spent just waiting for your number to be called, just like the DMV.
Questions asked: When did you get married?
Why did you marry?
Where did you meet?
Where was he living?
When did you visit each other?
Where did you travel together?