We did it! 96 people from 41 countries. Only a minority wear a suit and some actually wear jeans or even... a tracksuit. No tie either. With a sport coat, buttoned shirt and dress pants I was probably in the top 5% for attire.    No question asked when my wife only had a GC but they took my EAD/AP too. The person in front of me had 10 cards!   Overall a smooth experience. The judge was an immigrant himself (came with his parents and siblings) and took his oath in the same cou