It was a great experience. The USCIS office on Guam works really fast. Probably because of the small number of applications on the island. My marriage based interview was scheduled about 6 months after we submitted the AOS form.
After we entered, the interviewing lady was really nice. I feel like our case was really easy to work on. We gave a bunch of pictures but it was obvious that she had no doubt about our relationship. We pretty much checked all the filed information and answered a few questions about our relationship. When it was done, she told us that she is going to double checked everything and starts the process ASAP. The next day I saw my notification online that the card is approved and already sent to produce it. Today: 3 days after the interview I got a new update showing me my usps tracking on the Card.