I was flown out to Tucson, AZ and stayed in a rather nice resort outside of town where the hiring event was located. They definitely were trying to impress. The actual event itself was a lot of buildup to a meet and greet where interviewees could land additional interviews the next day. The interviews were at booths in a large ballroom and were relatively short. I was asked a few behavioral questions and a few technical questions about my background and thesis. Overall it was very conversational and casual.