I did the interview at SFO, they did ask me some of the questions I'd filled out though they were very polite, friendly even and I felt they were looking for mistakes like when you have to enter your email address a second time rather than grilling me for the prosecution.

They hadn't done many interviews yet when I was there and it turned into a group effort on their part. There was also a delay when my hands were too dry to scan and they sent me to the bathroom to wet my hands. Though all told, I don't think I was there for more than 15 minutes. Well worth the hassle saved at immigration.